Modem for rf cubscriber's telephone system

[Detailed Description of the Invention]

[Background of the Invention] The present invention relates to the modem for changing into the phase modulation intermediate frequency (IF) signal which generally starts a communications system, especially uses a bit stream for RF member telephone system. The outline of [invention The modem of the present invention has a modulation part and a demodulation section. A transmission section is a system from which each defined continuation number of bits changes into a phase strange tlllF signal the bit stream which defines one symbol in a predetermined intermediate frequency (IF). a modulation part -- 1 -- carrying out the phase modulation of each symbol -- 2 -- filtering the Gentlemen-phase-modulated symbol in digital one The abnormal-conditions signal of the modulation frequency which carries out a deviation according to the symbol by which consisted the center in predetermined frequency and the phase modulation was carried out [ above-mentioned ] from this center, The filtered signal which is brought about when changed into an analog signal is supplied, 3) Change the Hearth transfer(ed) above-mentioned signal into an analog signal, and bring about a Sorrow tone signal, further -- four -- the above -- abnormal conditions -- a signal -- predetermined -- frequency -- a normal signal -- mixing -- the above -- modulation frequency -- the above -- predetermined -- frequency -- abnormal conditions -- a result -- it is -- IF -- frequency -- having -- frequency modulation -- (-- FM --) -- a signal -- it is -- a phase modulation -- IF -- twice -- signal offer is made. The phase modulation IP double signal which the demodulation section of the modem received, this received phase modulation! The recovery system for changing into the bit stream by which the signal drawer was carried out F times is consisted. The modem of the present invention can operate in transmitting mode, receiving mode, time multiplexing transmission / receiving mode, or adjustment (trail-ing) mode. When operating in transmitting mode, the modulation part of a modem receives the digital 2 Advance bit stream of a maximum of 4 A bit per one symbol, and carries out IF time many phase modulation [ as ] signal transformation of this symbol of predetermined IP frequency 20.2MH2. This abnormal-conditions IF signal is transmitted to an RF device, and frequency increase conversion (up-conversion) of it is carried out to suitable UHF frequency, and it is transmitted to it. When operating by receiving mode, the receiving part of a modem receives phase modulation 1F signal from RF receiving set. A modem carries out the furnace solution of this receiving IF signal, and carries out frequency region (down-convert) conversion at baseband frequency, and digitizes the signal by Sp3 (Kilo-symbols per 5econd) to predetermined rate 16 of a symbol further at a complex (+, Q) sample. A digital FIR filter performs filtering processing further, and a complex sample is changed into a digital 2 Advance bit stream. This 2 Advance bit stream is outputted to a baseband device. A modem performs the function for providing symbol synchronous measurement, and various control and a status reporting function of the quality of a link further. The time interval which changes can be set and a modem can be set as adjustment (training) mode. In this mode, it is the abnormal-conditions machine and demodulator of a modem, In order to correspond to the change in the system (mainly filters of an RP device) which changes with attenuation of temperature or temporality, and a contiguity channel, or other environmental change and to adjust the FIR filter of a demodulation section, it acts as a loop back through an RF device. The Fil? filter of a demodulation section adjusts the coefficient, and it offsets all the poor filter adjustment in order to attain the best input signal state. The transmission section of a modem outputs the fixed adjustment pattern which is known to the demodulation section of a modem during this loopback. The FIR filter of this demodulation section adjusts that coefficient in itself [ signal ] according to delay, a progress signal, and the signal from an adjoining zone (train). The modem of the present invention is [especially with this application and the same day! ricPaneth and Mark J, The title of American 06th/of patent application 713,925 inventions by Handzel "they are single - or two or more channels about a multiplex sound and/or data signal communication. Are simultaneous. Member RF telephone system""5ubscriber RF Te1ephone System for Provid-tng Multiple 5peech andlor Data4ignals Sl-multaneously 0ver for carrying out In a radiotelephone system given in Either a Single o and r a Plu-rality of RF Channel'', it is useful. The desirable embodiment of a modem given in here interfaces with a channel control device (CCU) and an RF device given in the above-mentioned American patent application, and is related to this specification. The above-mentioned U.S. patent application is contained in this specification as a related document. about other features of the present invention, it indicates and comes out in relation to explanation of a desirable embodiment. The acronym used for this specification is explained as follows. A/Ro Analog digital converter AGC automatic profit adjustment AM amplitude modulation BPSK At least 2 Advance are phase shift keying abnormal-conditions BS. Base station CCU channel control device a mouth / A digital analog converter d8 Decibel DPSK Difference phase shift keying abnormal-conditions ECL an emitter conjoint form -- logic FCC Federal Communications Commission FIFO first-in first-out memory storage FIR owner j 1-hour impulse response filter Hz hertz (cycle 7 seconds) 1 The 2 Said Sum IF intermediate frequency KHz kilohertz Ksps Bit of a kilo ° symbol / second LSB lowest M) Iz Megahertz ?IODI1M modem (integrated abnormal-conditions and demodulator) OCXO furnace control crystal dispatch machine Q right-angled phase QPSK Right-angled phase shift keying abnormal-conditions RAM Direct access storage facility RCC wireless control channel R[! LP gas remains excitation straight line prediction RF radio frequency RFU radio cycle device (radio communication equipment) ROM Fixed storage RX reception STIMU system timing apparatus SOB Member office ↑DMA Time Division Multiple Access TX transmission tlHP Rash shortwave frequency VCXO voltage control crystal dispatch machine the desirable example of a modem -- the -- the [ 1A and ] -- it shows and comes out toB [ 1 ] figure. the modulation part of this modem -- essential -- a digital phase shift keying (to DPS) abnormal-conditions fixed storage (ROM) -- 10, Adjustment mode change device 1x, limited temporal duration impulse response (FIR) digital filter 12, digital, Announcer, log converter (D/A) Zone filter 14 which has 13 and center frequency 200KH2, mixer 15, and RF amplifier 16 whose center frequency is 20.2 MHz are provided. the demodulation section of a modem -- essential -- TMS 32010 type digital microprocessor 17, FIFO (first-in first-out) stack 18, and an analog digital converter (^/D) -- 19, amplifier 20, and mixer 21 are provided. This modem has several sorts of required timing and control device absolutely further in the abnormal conditions and Revival which a modulation part and a demodulation section perform, respectively. these devices -- status register 24, link Q register 25, AGC (automatic gain control) register 26.17X frequency register 27, and a member fractional delay register (SOB) -- 28, The phase (1) register 29, right-angled phase (quadrature phase) It has the interface register and bus controller 23 containing (Q) register 30 * control device 31 and 2nd fractional delay register 32. Modem timing and a control device are buffer control device 34, reading / write-in decoder 35, adjustment pattern FIFO (first-in first-out) stack 36, data latch 37, internal timing, and control signal generator 3B further, Transmitting clock delay device 39, fractional delay generator 40, VCXO interfacing unit 41, and sample time generator 42, It has direct access storage facility (RAM) 44.2KROM 45.4K RO146, a buffer / attenuation machine device 47, and buffer device 48 in CO3/SIN IF signal generator 43.2. t Connect with system timing apparatus (STIMU) 49, and a modem is. the interface of a modem -- the -- it shows and comes out to 1A and 18 figure. A modem receives the greater part of the input from CCU. Other inputs are supplied from an RF device and a timing apparatus. The input to a modem is as follows. the modem from a channel control device (CCU) -- TX D^Ding A: (line 50) -- the symbol (it is [ ary PSK / 16-] 1 A bit to 2 A bit and BPSK in 4 A bit and QPSK) of 4 A bit which should be transmitted by a modem. MOD Bus (51) : Bidirectional microprocessor which supplies control / [ from /] status information to a modem. MOD WR (rye y52) : f11+ control signal which carries out the Motheni latch of MOD Bus. MOD RD (line 53) : control signal sent out to MOD BIIS in order to transmit modem status and other information to CCU. MOORBSET < life 54 A modem is reset + Co (7) CCU 11M line. MOOADI+ (line 55): The control signal which defines various Adles memory site and the latched value in a modem. TX SOS: (line 56) The signal from CCU which makes transmission of TX slot start to a modem. RX SO3(line 57): The signal from CCU which makes reception of RX slot start to a modem. From an RF device (RFU) to a modem IF RX (life 58) : from RFU to a <7IF received frequency input It is 80 MHz (line 59) from a system timing apparatus (STIMLI) to a modem. : a base station or the 80 old lz ECL clock from member STIMU, and this are the outputs of XO in a base station, and are VCXO in a member office. It is Hz to 16. (line 60) : Mask TX CLK used in the base station from STIMU. SOMF (line 61): Mask frame start signal used in the base station from STIMU. This is sent to CCU with a modem, without Use N Being carried out. The clock of the 16-kHz signal and signals which give TX CL symbol transmit timing from a modem to a channel control device (CCU) at :(line 62) CCU is carried out into a modem on the standup edge of this signal. In a base station, all the slots have the same mask TX CLK. All the signals from a base station are simultaneously sent out by this. In a member office, only a cell Sinal range delaying amount is offset by a modem based on the information to which TX CLK was supplied by CCu. RX CLK (line 63): 2 clocks of 16KH are drawn from a received signal (received signa1). (at the time [ Always setting to a base station in a member office. ] of control slot acquisition). 8 to which this clock gives a receiving symbol (received 5yvbo1) to CCU, and gives clock out (clock out) L and CCt+ symbol timing RX DATA (rye 764) :RX CLK D -- receiving symbol of 4 A bit by which the clock was carried out. FIOD 8115 (50) : Status and data information from a modem. MO Mouth SOMF: (line 61) Transmitting SOMF/from STIMu to CCU in a base station (forwarded SOMF/). AM 5TROBE (line 65) : if the change on a low level from a high level takes place with this line, a rough frame marker (rough fralle marker) will be given to CCU at the time of the wireless control channel (RCC) acquisition in a subscriber device. This is a one shot line started when RX 7MS320 determines the approximation memory site of AM hole. From a modem to each RF device (RFt1) RF RX BIIS (66) : Bus of 8 A bit between -t-Dem and a RF RX device. This bus transmits AGC and frequency-selective information to a RFtl receiving part. A modem controls the AGC value which should be sent out and 0 frequency-selective information that CCU frequency-selective information is transmitted is supplied to a modem through MOD Bus 50. During the ai ready mode, a modem controls selection of RF RX frequency. RF TX 8115 (67) Bus of 8 A bit between Knee 1-Dem and a RPIJ transmission section. This bus transmits TX electric power level and frequency-selective information to a modulation part. A modem is unrelated to these pieces of information, and these pieces of information is only transmitted to a RFtl transmission section. RX80MH2REF (line 59a) : ECL to a RFLI receiving part 80-MHz reference clock. TX80MHz REF (line 59b) ECL to :RFU transmission section 80-MHz reference clock. TXEN(line 68): The line to the Me (7) RFU transmission section which enables Rp transmission. RXEN(line 69): The line to the RFU receiving part for enabling RF reception. AGCWR(rye: /70): Writing for latching AGC data to an IIFU receiving part, Strobe. RXFREQ WR(rye 771): Write-in Strobe for RFU receiving part Heno frequency writing. RXFR[! Reading Strobe for reading the received frequency (receive frequency) from a mouth ■:(line 71a) RFU receiving part backward (readback). P Chestnut RHR (line 72): He is write-in Strobe of RFtl transmission section transmission section child latch Bread about electric power information. PWRRD: (line 73) The reading list rope for reading the electric power information from a RFU transmission section backward. TXFREQ RD (rye 774) Reading Strobe for reading the transmit frequency from a lF[l transmission section backward. TXFREQ WR(line 75): Write-in Strobe for the frequency writing to a RFU transmission section. IF TX (rye 776) :RFU -- (life '17) To (D, transmitted signal (Transmitted signa1) 5 AGCl?I whose frequency is IP cycle): -- reading Strobe for reading the AGC data from a RFU receiving part backward. A modem to system timing-apparatus (STIMu) VCXOFORK: (rye 778) The data bus of lO bit to VCXO including the control information for frequency tracking. VCXOW+? (Rye 779) : write-in pulse to the vcxo circuit which carries out vCxO Nirach of vcxo BLIS. The modulation part of a modem transmits the information supplied to the modulation part of the modem by CCU through TX DATA line 50 in the PSK abnormal conditions of 16 levels. In this case, a modem (it transmits without getting to know the abnormal-conditions level of the above-mentioned information to be received.) It is compounded within a modem and an input control line is Mo1l BIIS of 8 A bit between a modem and CCU. The register which drives 50 is chosen. If a modem receives the RX SOS signal on line 57 from CCU, this line to which the control signal about slot reception becomes effective (active) will apply interruption to microprocessor 17 in order to start the recovery of ON Kaslo y (incoming 5Iot). In this case, a RFU receiving part becomes usable with a modem by the RX EN signal of line 69 (enabled). For every end of each slot, status information is updated by register 23 and reading of CCU is equipped with it. CCU can emit instructions to a modem and can make it acquire a RCC signal from a base station in a member office. The main acquisition function of a RCC signal is AM ll0LE of eight symbols. In software, a modem scans the frequency which CCU chose to AM HOIJ. Microprocessor 17 scans the frequency which CCU chose to 8M HOL[!. When AM HOLE exists in this frequency, keying-in (key in) of the microprocessor 17 is carried out at it. After microprocessor 17 checks existence of AM ll0LH, a ccu D pair is carried out, and it is A.I. Artificial Intelligence'l STl?OBl! Line 65 is started on a low level, and the following things are expressed, namely, having acquired (1) RCC signal and +21AM 5TROBE should be in a sparse frame marker start. From this time, CCU should start search of unique word (unique word) in RX data stream of 0~3 symbol within the limits. If this unique word is detected, CCLI of a member office can adjust that frame and slot counter, and can unite them with the system frame of a base station. The interface between a modem and a RFU receiving station enables control of the frequency selection in RFU, and an AGC level. CCU controls frequency selection and transmits the command of CCLI to MODEM. A modem transmits this information to IIFII by RX I?F BtlS 66. This bus 66 is further used also for control of the AGC level in RFupsilon receiving station. These AGC values are updated for every time of a symbol, and are transmitted to a RFU receiving station. A CCU modem interface is an example in Drawing 1. The timing to a transmitting interface is an example in Drawing 6. Since these interfaces are low speeds, they need only the interface of standard TTL hardware. A modem gives a 16-kHz symbol clock to cCu. Four TX DATA bits exist in the parallel bus to a modulation part. Since the bus of 8 A bit is exchange of control / status information, it is prepared. Control information is supplied to a modem by CCU through asynchronous interface register 23. When Strobe TX SO3 signal of line 56 is received by the modem, it comes into effect, and the contents of this register show the transmission start of a slot. +11 pause mode in which CCU provides a modem with the following control information, (2) transmitting audio channel, (3) a transmitting control channel (41 adjustment mode loopback and a (51TXCLK decimal symbol delay, [6) RFTX electric power level -- and (?lRF/TX frequency selection and RF frequency selection are memorized by RX frequency register 27.)), CCU is M (it has directly an interface which passes through buff 77 system 'a device 34 from l[l BIIS 5 Q, and results in a Te RF TX Bus 67 Heno RF TX device.). The decoded address is supplied to RFIJ as write-in Strobe for latching TX electric power and TX frequency information. Since [ this ] the modem must have a right of control of RFRX bus 66 for the renewal of AGC to RFU, at the start time of each RX slot, a modem transmits RP frequency information to an RF device from register 27. This value is latched to register 27 by CCU. Outside this, the modem can change the RF frequency itself during the I ready mode by - which does not need intervention of CCU. The symbol which the modulation part of the modem is completely functionalized in hardware, and does not require adjustment at all is received [ per second 16 ] by Ding X DATA line 50 from CCU at the rate of a symbol. A receiving symbol (receivedsys+bols) is orthopedically operated with Fi11 filter 12, in order to obtain a waveform without the amplitude which becomes a phase modulation is carried out by DPSK conversion ROMl0, and the waveform which arose as a result has the outstanding interference characteristic, and disadvantageous, or group delay distortion. It is assumed that it does not have a powerful interference signal (what has electric power density larger 30~40 dB than a symbol) in the frequency band (within the limits of 50~100 kHz) which approaches the zone currently used as a basis of this view. It is [ filter / 14 / 200 kHz zone / signal / (trans-witted signa1) / transmitted ] Amena in amplitude or group delay distortion, it is -- ' -- all the harmonics generated by D/^conversion which performs broader-based IFtFf wave processing (100 kHz) like, and is performed with digital furnace solution processing and base band (baseband) are removed. Main Filtrate processing is performed by digital FIR filter 12 of a fixed coefficient with a base band. This filter is 6 pole filter in FIR filter 12 of a modulation part which has sampling speed of 50 samples for every symbol during the symbol. Since analog Filtrate processing is not performed in a base band, it is not necessary to use two different I and Q channels. In fact, ■ and Q channel are used with FIR filter 12. One time sharing channel containing mixer 15 which carries out the increase in frequency only of the IF frequency carries out high frequency number-ized conversion (upconvert) of this channel to IF. This channel! And it has an equal profit from the first to Q samples. This is corrected by FIR filter 12 although the bandwidth of I and Q sampling is [ the half of the sample period ] alternate at present. Gray code (Gray code) is used for the digital coding by conversion ROMl0 at DPS. This guarantees that the error of a decryption symbol is only 1 A bit also in the greatest probability, when a symbol is received accidentally. A signal group (signalconstellation) is an example in Drawing 2. It shows and comes out by 'Q'' and '''B", and a certain phases are QPSK and a BPSK symbol, respectively. A symbol is taken out and turns into a GlrAY coding phase symbol. All the symbols are changed into 2 Form from Gl?AV numerals, are added to 2 Form of the last phase symbol, and form a symbol in DPS. All other symbols are reversed by the algorithm of a FIR filter before being inputted into FIR filter 12. Therefore, DPSK conversion is ROM. It is carried out using 10. One bit for four bits, four bits from a front symbol, and reversal control is inputted into DPSK conversion ROM10, and DPSK ROM 10 outputs a DPSK symbol to the input of FIR filter 12. A symbol is supplied to line 80 to FIR filter 12 which is a (oversampled) FIR filter in which the Oba sample of the 6 Tasov was carried out after DPSK conversion. FIR filter 12 has shift register 82.83 of ROM81, two 3-stages, and 4 A bit, as shown in Drawing 3. FIR filter 12 has achieved the role of waveform shaping of a transmitting symbol according to the specifications of a frequency channel. The sampling speed of ROM 81 is decided by the timing signal supply ° Made into line 84 from timing and control signal generator 38 to counter 85 of connection with ROM 81. A large power clock signal is supplied to line 86 to two input switches 87.88 which make possible the data input to shift register 82.83. Reference of Drawing 4 will carry out the sample of each of six symbols in two shift registers 82.83 at the rate of 3/25T (T-1 / 16 kHz). As for the method of this oversampling, the sample only of the two symbols is carried out to any one sampling period of 1/25T, The skew (skei1) of the sample is carried out, therefore two symbols are inputted into ROM81 during [ each ] the sampling of 1/25T. It is divided during the sampling of 1-/each 25 T the place got blocked during two portions, i.e., the period of a phase (I) phase and the right angle (Q) phase. Registers 82 and 8.3 input the in-phase component (1) of 3 A bit of a symbol early in the period of 1/25T, and the right-angled ingredient (Q) of a symbol is inputted into ROM81 in the second half of the above-mentioned period. Thus, digital of the waveform to which the FIR filter output of line 89 should be transmitted by which time sharing was carried out! And it becomes a waveform of Q. These samples are supplied to line 89 to D/A converter 13 after this for conversion to an analog-spectrum form. A furnace solution is carried out to this waveform with zone filter I4 next, and line 91 to mixer 15 is supplied for frequency increase conversion (up-conversion) of 20 MHz IF time signal of line 92. Two shift registers 82.83 are ROMs at the speed of 1/25T. Two of the gin pole memorized by 81 are shifted and it prepares for necessary calculation. These symbols are changed into ■ of 3 A bit, and the gray code of Q by choosing either of the 4th or 3rd symbol as top A beat l- (MSB) of a 3-bit ingredient. This ingredient selection that remains the same as for two least significant bits (LSB), and does not change is performed at the rate of 1150 T. 1?OM needs five inputs from computer 85, in order to know further any of the sample periods of 25 are calculated now. One additional input from computer 85 needs a 3-bit input in order to tell ROM 8] about whether it is I ingredient of an input symbol, or it is Q ingredient. Output signal memorized in transmitter FIR filter ROM 81, And it is calculated for all the error corrections with the probability which occurs by the time lag of 1150T of the time value of Q. Although IF filter in I?FLI adds these two values together and forms the right transmission waveform, this is because that wave-like bandwidth is relatively narrow as compared with IF frequency. FIR filter ROM81 brings the digital sample output of 10 A bit to line 89 at an 800-kHz rate. Since the symbol which does not have transmission power is expressed, a NULL symbol can be poured into FIR filter 12. These symbols are used for an ON dregs To sake by FIR filter 12 in an "impulse" in adjustment mode. Since AM HOLI!S and the protection zone which are further needed by a wireless control channel (RCC) are outputted, these NLILLS(s) are used. D/A converter 13 takes in a digital input from digital FIR filter 12, starts in 66.67 kHz, and makes the necessary spectrum of a 133.33-kHz multiple. As for zone filter 14, pass band attenuation and change of group delay pass a 200-kHz spectrum very small to a degree. Attenuation Rippl is 0.1 dB or less, and delay change is 1.5 microseconds or less. A fake signal (alias-1ng) spectrum of 20 dB or more is attenuated. The request signal from D/A converter 13 has the center frequency in 200 kHz, and the bandwidth is about 32 KIlz(es). This signal is a zone by zone filter 14 before the mixing process for removing the signal ingredient of Hz to nx133. - By multiplying the waveform of 1 200KH2 by which a wave is carried out by 20 kHz, mixer 15 mixes ! and Q samples by SIN and eight ingredients of COs of IP Frequency loss. Thus, the 20-kHz signal can multiply an output waveform directly, and exact ingredient multiplication will be processed automatically. For this reason, individual 5IN(IF)/for becoming as [ be / it / in a demodulation section ], and multiplying the I/Q sample from /A (a 705(IP) generating circuit is not needed) This removes the separation feeding through (isolation feedthrough) in mixer 15 to the output of mixer 15 from baseband further. Buffer attenuation device 47 receives an ECL level signal discriminatorily in the intermediate frequency of 20.OOMH2 of line 94 from timing and control signal generator 3B, This signal is changed into the 350IIIv beak peak signal used as a local dispatch signal supplied by line 95 to mixer 15. Another voltage voltage divider (not shown) supplies the +7.5VDC bias to mixer 15. Mixer 15 is a MC1496 active mixer. 2 by which ■ from line 91 and Q ingredient waveform are supplied to this mixer by line 92 with other mixer outputs of all the IF crack signal frequency conversion of 0.20MH2 -- it carries out. A 3rd middle abnormal-conditions output receives attenuation of 40 dB or more. About a subcarrier input port, mixer 15 is high-level, operates, and operates on a low level about an abnormal-conditions signal input boat. Thereby, it is saturation switching operation about a subcarrier double differentiation amplifier, since the subcarrier of -20 and 00M1fz which brings about alignment operation about an abnormal-conditions differentiation amplifier is removed by the 20.20-kHz crystal filter in RFLI, subcarrier Null (nul1) does not arise -- the current source is set up to supply the current to 2-. The emitter degeneration resistor (not shown) of 47oomega is provided in order to maintain an abnormal-conditions signal input to the alignment working range of a 1-v peak. RF amplifier 16 has brought about 50-ohm output impedance while having an emitter follower buffer for avoiding interference of a mixer tuned circuit and RFF1a. Since the influence of Straying electric capacity, device capacity, and the capacity of the emitter follower which eases a mixer input is removed, it can side with a mixer output at the maximum profit using a parallel tuned circuit. in the output of a modem -- 50 ohms -- 1 -- since 10 dB is required, the rest can use not a variable inductor but the fixed inductor whose comprehensive profit of a mixer must be 10 dB for a When (later) mixer output tank circuit. RF amplifier 16 amplifies the signal of line 92 from the output of mixer 15, and supplies the amplified signal to RFtl through IF-TX line T6. The modulation part of a base station modem transmits the pause pattern given by CCU between pause modes. In a member office, since the modem is operating by half duplex, except for the slot period which the member office itself is transmitting, ccU sets a modem as receiving mode during [ all the ] the slot. This makes AGC supervise to the demodulation section of a member office modem, and when a burst signal jumped in and comes from a base station, it is kept from suddenness being struck. Pause mode is used when the frequency from which not all the slots but at least one slot serves as a candidate for use exists. When all the heat conversion of the 0 frequency into which an empty slot is filled up with a pause pattern is not carried out, a modulation part will be in a non-use state (dJsabled). If the demodulation section of a modem is referred to, mixer 21 will present 50-ohm input impedance to IF-RX line 58 to the signal of 20 *OOMH of two to 30 dB received from RFU. The basic function of mixer 21 is amplifying only 30~35 dB while carrying out frequency region conversion (down-convert) to the IF time signal baseband from RPII. The normal signal is supplied to line 22 by 20.OOMIIz. This normal signal of line 22 is time To multiplex [ of CO3/SIN IF generator 43 ] h Tha SIN/CO3/-5IN/-CO3 signal. motel MC1496 active mixer 21 -- line 58 of the local dispatch machine input signal of line 22 of a high level, and a low level -- -ed -- strange -- (sodulated) the "Jf4 signal is impressed and used. It passes through the mixer output of line 97 of baseband discriminatorily to amplifier 2o which is a differentiation amplifier, and O combination of it is done. A height filter is formed of the capacitive coupling from mixer 21, and the capacitive coupling from the input resistance machine of differentiation amplifier 20, and this high pass filter has cutoff of abbreviation IHz. Buffer device 48 gives an interface between ECL level 20. OO old 1z generator 43 and mixer 21. Buffer device 48 is put while it brings about the 350-v beak peak signal for driving a subcarrier input into saturation switching (saturated switching), and it gives the bias of +7.5VDC to an input. IF SIN/CO5 generator 43 is an example in Drawing 5. This generator 43 consists the ECL parts which answer timing and the INF timing signal of line 98 from control signal generator 38, and operate by 4 times of pursuing (tracked) IF frequency. If Drawing 5 is referred to, two flip flops 99,100 act as an A counter, and it is carrying out 90@ phase gap of each of this output. 4x1 multi-pre Tucusa (MIX) 101 performs Misplacement of SIN, CO5, -3IN, and -CO5 output. MIIX Re-Rolphuk of the output of 101 is carried out by other D Flop 102 (reclocked), and it is outputted to line 103 to mixer 21. This circuit brings about 90 phase gaps correctly among the four above-mentioned ingredients. The single time multiplexing channel has guaranteed the fact that I and Q ingredient are further inputted on an equal profit correctly (arrive). The timing diagram of a demodulation section is an example in Drawing 6. A modem gives four data bits and those 16-kHz symbol clocks to CCU. The bus of an address line and 8 A bit provides status / control exchange (status/controlinterchange) between the two above-mentioned 1 Place. Acceptance puts in the differentiation output from a mixer and amplifier 20 of about 25 dB amplifies this. Amplifier 20 passes through the ±10-v peak peak signal of AC combination in the almost distorted state where there is nothing, and gives it to /Rocon barter 19. TRW AID converter 19 which is A/[1 converter of 12 A bit is used in order to change the baseband spectrum from differentiation amplifier 20 into digital data for processing by microprocessor 17. Sample speed! It is 4 times per symbol. Digital processing is performed by TMS 320 microphone Lopro sensor 17 during normal operation. Microprocessor 17 is a byte from 4KROM46 to 4. It operates at 20 kHz by a memory. The boat address pin is used in order to carry out the address of the Ilo register between a demodulation section, CCU, or a special diversity combiner circuit (combier circuit). Microprocessor 17 receives I10 data from mixer 21 at sampling speed of 64 kHz. Time multiplexing of this data is again carried out by one frequency channel like the processing in a modulation part. Microprocessor 17 carries out wave-like Filtration treatment and recovery processing. Microprocessor 17 outputs a receiving symbol (received signa1) to data latch 37 by bus 104 after that, This data latch 37 provides this symbol to CCU through RX OAT^line 64 at the rate of 16KIlz with the pulse of the RX CLK signal of line 63. It is stored in status register 24 and the status (state) of a receiver is I10 sample! It is stored in register 29 and Q register 30. CCU will read status, as long as 1/Q sample is required to an external diversity combiner circuit. The interface and its function of System m / status are explained below. Operation of the base station modem is assigned to fixed RF frequency. Communication in a base station is full-duplex-ized. Therefore, the modulation part and demodulation section of a modem are operating simultaneously. When a modem is further assigned to a control frequency channel modem if possible, it is only transmitting and receiving information with wireless control channel (RCC) form during [ when the modem was assigned ] the control slot. in a base station -- a system timing apparatus (STIMt1) -- it is fixed and the 0CXO in 49 operates as a mask clock of a system. Therefore, a gap of the frequency for reception does not occur. All the transmission from a base station modem is masters TchiCLK of line 6 *. Signal (16 kHz) timing is taken (clocked) -- the decimal time delay generator (fractional time dslaygenerator) in * base station modem -- 40, The fractional part of the symbol time during derivation (derived) RX CLK of line 63 in a signal and a modem is given to base station CCU at master TX CL of line 60. This information is sent out to a subscriber device via a wireless control channel so that a member may delay that transmission, so that the signal of a member office may do * synchronization of at all other slots and may be received in a base station after this. All the operations in a member office modem are drawn from the (recoveved) receiving clock signal recovered by timing and control signal generator 38 from the contents of reception (received) transmission (de-rived). (to RX CL) This signal works as a mask clock of a member office. A signal is not a mask clock so that in a base station to TX CL of line 62 from transmitting clock delay circuit 39 to CCU. This signal is drawn from the RX CLK signal of line 63, and receives delay by transmitting clock delay circuit 39. Such delay temporal duration (duration) is given by CCU of a member office, and decimal delay (5alumnus) register 28, and is taken out from this register 28 by transmitting clock delay circuit 39. CCU of a member office receives this delay from CCt+ of a base station through a wireless control channel. The distance between a base station and a member office determines this delay. CCU of a member office supplies this decimal time information to decimal delay (SOB) register 28 in a modem through MOD Bus 50. The modem itself takes in this decimal delay through transmitting clock delay circuit 39. When CCU inserts TXSO8 signal of line 56 in the modem with which only the exact number of symbols is receiving delay, this processing that processes integer symbol delay adjusts the signal which receives a message from all the member offices of a different distance in a base station. Many sources of delay exist in a modem system, and it has remarkable influence on the timing of a system. As these sources of delay, they are analog filter delay, a propagation delay, the process delay of FIR filter 12, etc. These delay must carry out the skew of the frame of TX and RX mutually, and must pay detailed consideration. The guess delay value was attached and the delay course from a modulation part to a demodulation section was shown below. Tta : TX analog delay. Abbreviation 0 *55TTtr : Transmitting delay between TX and RX in an RF device. About 1.9T Td : propagation delay. A maximum of 1.27 (one way) Tra : RX analog delay. About 5.77 TTh(s) : Time during the sampling of RX analog filtering output before AID conversion. About 0.03 T Tc : A/D conversion time. It is Off in order to receive the peak in about 0.22 TTf+ and Tfz:RX FIR "rye 7 F One" 1 time t= 0. Ilta is Sun Puri in t=TL. Tongue processing must be started and it must continue to Tf (about 3.57') and Tfz (about 3.25T). To The process delay between : "peak" and 7MS outputs, about 4.5 T Tw : Long fence 6T of TX waveform. Tcrt : it is [ as opposed to / the minimum and these days / a member office ] the maximum to the compensation delay between RX and TX (member), and the maximum Far-end subscriber office. SBn: These days member office. sBr: The maximum Far-end subscriber office. The time delay between receiving analog symbol [ of the beginning in TX SOS and the base station in a base station ] - "peak" is +7.4 symbol. Therefore, a skew exists between TX slot and RX slot. In order to decode an input phase (inco+ming phase) correctly, the modem must start sampling processing before arrival about 3.5 symbols of a "peak." Therefore, the skew between TX SO5/and the starting point of RX sampling becomes a length of about 4 samples. In a base station, the start of RX slot occurs at the time of after-start abbreviation 4 and T of TX slot. The analog sample of the beginning for detecting first 1 peak "received taking-in time is defined as the starting point of an IIX slot. The modem of the maximum Far-end subscriber office starts the TX slot before start 4T of the I?X slot of the modem of a base station. Other member offices can delay the start of the TX slot. In 17F telephone subscriber system, the both-way transmitting delay resulting from distance occurs everywhere in O~3 symbol time length. Therefore, since the reception telephone call in a base station changes into a synchronous state, the member office can carry out the 0~3 symbol time shift of the transmitting clock about a derivation (derived) receiving clock (RX CLK). Time delay is calculated in a base station, and is sent out by a control channel, and is decoded by CCU. CCU gives a decimal delay constant to the modem of a member office in order to delay TX CLK. Decimal delay is a value of 8 A bit written in decimal delay (SOB) register 28. Integral symbol delay is controlled by CCU. Strobe TXSO5 signal of line 56 follows the distance value received from the base station -- 0.1 -- or two symbols are delayed and it generates. A modem carries out frequency synchronization-ization by acquisition of a slot and vcxo is under control of microprocessor 17 directly through the moiA converter in Si CXO ink face 41 in Continuing and a member office about pursuit at the time of reception of all the slots. Cycle acquisition and pursuit algorithm of microprocessor 17 calculate change of cxo in necessity, in order to maintain a synchronization. Microprocessor 17 also carries out bit synchronization-ization about the bit synchronization pattern (bit 5ync pattern) of a data stream to be received at the time of reception of all the slots. An algorithm accomplishes bit pursuit Le and - A. In the inside of the bit pursuit loop which has control power to the variable frequency counting-down circuit of 80MHzVCXO or ocxo (at the time of a control slot recovery), microprocessor 17 changes a frequency part circumference, in order that microprocessor 17 may attain bit synchronization-ization. Although a Divide value has 0.1% of step size (step 5ize) of 16 kHz at the time of reception of an audio channel, a Divide value is [ one layer of When ] large, and it can make it change +/-50% at the time of a control slot. Frame synchronization-ization is processed by the method of being completely different in a base station and a member office. In a base station, it is mask soMF. A signal (start of a modem frame) is transmitted to rye * A 61 to CCU via a modem. This is a master SOMF signal used for all the transmission from a base station. CCIJ can draw all the slots and frame timing from this signal and the mask system symbol clock signal (16 kHz) of line 60. Initial inspection -- while it is profitable, microprocessor 17 searches for AM HOLE in RCC in a member office. When AMHOLE is detected, microprocessor 17 counts AM HOLE to the frame of 2.3, and it is AM 5TIIOBI to timing and control signal generator 38! A /marker is made to supply to line 65 to CCU in the frame position of AMIOL[!. CCU does the cent rise of the initial frame marker counter which can be changed by CCU software, in order to use this strobe marker and to obtain an exact frame synchronization (window wing (windowing)). The trimming of a figure and this mean that AM HOLI! was detected and RCC was acquired again. Slot synchronization is under control of CCU. Signal TX SO3 of line 56 and signal RX SO5 of line 57 are the commands to the timing and control signal generator 38 for starting transmission or reception of a slot. These signals synchronize with the TXCLK signal of line 62, and the RX CLK signal of line 63, respectively. The demodulation section of a modem operates in either off-line mode or on-line mode based on bit 7 of RX control word of control word register 31. In order to switch a demodulation section to the mode of another side from one mode, CCU sends out MOD RESET, and it is NOD Bus. A necessary command is written in RX control word register 31 via 50, and a HO mouth RESET signal is cancelled. In off-line mode, a word is given to the external memory of a microprocessor from a word and RAM from ROM 2 2. At the time of un-transmitting of a modem, or un-receiving, CCU emits instructions so that a modem may perform a self-examination and an adjustment routine, and this signal may be inputted into a modem for every regular breadth in ken after Stand top bj (afterpower up) and everywhere. A self-examination routine examines 120M45.46, internal 1?AM, and external 11AM44 and the interface to CCU. This routine sends out a test result to CCU through status register 24. This routine including that an adjustment routine sends out an adjustment signal to a demodulation section and calculating the coefficient of FT11 filter included by microprocessor 17 is everywhere carried out off-line for every regular breadth in ken at the time of the non-data transmission of a modem, or non-data reception. In on-line mode, a modem receives a signal from either a control channel or a voice slot according to the RX section control word of control word register 31. Online software performs the following routines. An initialization routine is started (power up) and carried out as microprocessor 17 Nyoto the time or after reception of a Risent signal. This routine reads the control word of register 31, and calls other routines according to this control word. as for this routine, CCU receives a modem -- line 54 -- NoORES[! T signal -- and it is started when a command is sent out by MOD BUS 50 to control register 31 for an on-line mode input. This routine performs the checksum (checksus) examination about on-line FROM, initializes a parameter, and reads control word register 31, and branches to a suitable routine. A frequency acquisition routine is performed only with the modem of a member office at the time of As much as possible which synchronizes member office VCXO frequency with the crystal frequency of a base station, and control channel reception. Since transmission, reception, and IF frequency are pulled out from VCXO of a member office, or 0CXO of a base station, this routine has all the frequency in a synchronous state, and is crowded. This routine is used only in the modem of a member office. This routine is started by Command from CCU when the demodulation section is set as control channel frequency. Synchronizing VCXO frequency with the frequency of 0CXO of a base station has a function of this routine. This synchronous processing starts to search for short-time AM HOLf! to which transmission from a base station is not performed first. A base station transmits an unmodulated subcarrier signal (unmodulated carrier signa1) after this search. If this waveform is received, IF mixer's output will serve as another sine wave waveform which has the frequency proportional to the difference of VCXO and the frequency of the crystal dispatch machine of a base station. Modem software carries out the sample of I and the Q channel with the time interval which changes, and is a phase lock. A loop function is performed, namely, change of the phase to each time interval is determined, and this phase change is led to a low-pass filter, and it sends out to vcxo by making this into a correction word. A modem judges that acquisition of frequency was attained, when it becomes below a level that this phase change comprises. When not detected by within a time [ which AM hole comprises ], a modem shows that send out an error message to CCU and the receiver is not being aligned with a control channel. It is shown whether this routine was called by the initialization routine, the status word was sent out from status register 24 to CC[I, and frequency acquisition was attained. When an initialization routine receives a call, a frequency acquisition routine is a sake of AM hole search! And the sample of the Q channel is carried out, When AM hole is not detected within the period of the predetermined sample number which forms an AGC loop simultaneously, this routine transmits this information to CCU via status register 24. CCU is switched to the RCC frequency which may be another, and reboots a frequency acquisition routine. It passes and this routine provides the phase lock loop between the time when un-strange me wave transmission is transmitted after detection of H hole. In this loop, the phase angle of the signal by which ■ and Q samples were taken and the sample was carried out is calculated. The calculated phase angle is subtracted from a former phase angle, and low-pass filtering of the subtraction result is carried out, and it is sent out to vcxo as a control word. using signal amplitude -- during a loop period -- eight -- GC(s) are also calculated. When a gap of a phase is below a predetermined quantity in the end of the specified temporal duration, a modem sets "1" to status register 24, and when a gap of a phase is more nearly still than this quantity size, "2" is set to status register 24. In the case of the latter, a frequency acquisition routine can be rebooted into one or more slots. A bit synchronization-ized routine can be performed with both a member office modem and a base station modem the time of reception of RCC, and after completion of a frequency acquisition routine. In the modem of a member office, the output is used in order to synchronize a 16-kHz symbol clock with transmission of a base station. In the modem of a base station, an output is used in order to determine the decimal delay which should be included in member office transmission in order to acquire simultaneity with the modem clock of a base station. A slot receiving routine is called, when a modem changes into a data reception possible state, namely, after frequency and a bit synchronization are attained. the prime function of this routine -- initialization (starting of a symbol receiving routine when the sample of the symbol of bl beginning is carried out -- and (the determination of all the qualities of an after [ symbol reception ] link of Cl slot, and other information -- it comes out.)) of the parameter for a lal symbol receiving routine (it explains below), This routine is called by the initialization routine at the time of the start of each receiving slot. The prime function of this routine is initializing the parameter for a symbol receiving routine. After completion of this task, this routine branches to a symbol receiving routine waiting and after that until all the samples of the symbol of the beginning in a slot are recorded on FIFO stack 18. The processing task of this routine is as follows. 1 system '111" -- a MLO value may be 2.4 or 16 in reading abnormal-conditions level ML in - Do register 31, and here. Calculate 2 and the half symbol (1161[sy+wbo1) given by the following formula. Calculate 3 and gate^SK which uses LSB for a To truncate sake from the phase to which it restored. MASK is MASK= 8 X 2'(ML = in case of 2) =12X2' (card = in the case of four), supposing 2'' expresses the phase angle depending on the number of bits used since skin and the phase to which it restored are expressed which is 22.5 degrees by this. = 15x2'(in case of ML-16) 4 Former AGC to this slot is read in AGC register 26, and this is sent out (as opposed to a base station). branching to a symbol receiving routine waiting and after that till the end of the sampling to the symbol of 5 and the beginning -- and Send out the nature signal of a link to CCU from link prize register 25 after all the symbol reception of 6 and the above-mentioned slot. A symbol receiving routine is once started for every symbol period at the time of data reception, and the function receives the fal symbol which is as follows! And thing for which Q samples is read, a mountain -- filtering I and these Q samples (the symbol (transmittedsymbo1) transmitted C1 is determined and this is sent out to CCU), A fel bit pursuit algorithm is performed [ executing a phase lock loop, in order to synchronize [dlvcxo with an input (incomtng) signal, ] (Accumulation the information for calculating fl A G C and the nature calculation of (g) link.), This routine is once started for every symbol, when all of four samples about one symbol are memorized by external FIFO stack 18. This routine reads this sample into a memory, and determines the symbol which processed this and was transmitted. The gap (deviation) between the received symbol and the transmitted symbol is used for AGC, the quality of a link, and a pursuit algorithm. The execution time of this module is shorter than 1 symbol time, i.e., 62.5 microseconds. The specific symbol which changes is received! And this routine performs the following tasks after reception of Q samples, and memory. 1, the received FIRtF wave of a sample (a FIR4% loss is determined by the adjustment routine explained below). Determine 2 and a signal level and use this for AGC. Determine 3 and the received phase angle, subtract with a former phase angle, round a subtraction result, gray-code-ize the rounded result, and send out a coding result to CCU. Perform 4 and a bit pursuit algorithm. (This output is Accumulation(ed) about all the symbols, and is sent out at the time of the end of a slot.) This is used in order to synchronize a member RX clock with transmission of a base station. s In order to synchronize vcxo with the oscillator of a base station, execute a phase lock loop. (This by which this output is sent out to VCXO at the time of the end of a slot is used only in a member office.) Reach and send out information to ccU via nature register 25 of a link at the time of data Accumulation for the quality of a link, and the end of a slot. The internal clock signal which a modem needs occurs with timing and control signal generator 38 from the mask 80kHz clock signal of line 59. A modem is used as TX CLK for transmission of the mask 16kHz clock signal of line 60. For this reason, all transmission from a base station synchronizes mutually. The clock signal of a member office is completely pulled out from master 80kHz VCXO of a member office timing apparatus. This VCXO is vcx of line 78 from a modem. It is controlled by the PDBK signal. All the reception and transmitting clocks are calculated by VCXOFD8 of line 78 from the signal. Timing and control signal generator 38 give after this 16kHz RXCLK signal of line 63 pulled out by CCU from the input data stream. CCt+ detects the unique word in a control channel, and is unique at itself. A frame and a slot marker can be determined from a word and the RX CLK signal of line 63. The AM 5TROBB signal of line 65 tells CCU about the place which should be searched in order to be drawn from the signal modulated by microprocessor 17 by timing and control signal generator 38 and to obtain - unique word. In a member office, microprocessor 17 adjusts timing by calculating and time [ VCXOWR ]-signal-STIMtl-49-constant[ VCXOFDBX(ing) and ]-outputting a bit and a frequency pursuit parameter. In order to adjust frequency, microprocessor 17 is outputted to the D/A converter within vcxo interface 41 which supplies voltage to VCXO. This vcxo is Divide(ed) by five and set to 16 kHz. This 16-kHz clock is again Divide(ed) by 5, and generates a 3.2-MHz clock. sample time generator 42 which timing and control signal generator 38 Divide this by 4, and makes an 800Kllz Cros y person signal required for TX FIR filter 12, Sample time generator 42 which Divide a 3.2-MHz clock signal by 50, and makes a 64-kHz sample clock signal is under control of microprocessor 17, and generates delay at the time of control channel acquisition. Thereby, a lot of jumps of the ±16-kHz clock cycle for high-speed acquisition are made possible. Self-adaptation (self adapting) adjustment mode is in the loop back state where a modem goes into adjustment of the digital FIR filter factor of the demodulation section memorized by microprocessor 17, in order to correct degradation of all the analog filters by temporality or a temperature change. This analysis is conducted by carrying out loopback of the transmitter data through an RF device, and receiving the known pattern (known pattern) of the demodulation section of a modem. The above-mentioned coefficient is 5 restrictions lug Ranshu. . (5 constraint Lagrangian) It is optimized by a method. The data stream by which these limitations were il(ed) + received, the data stream in which only +210.057 received delay, +The 1st place is a data stream from a channel, and a data stream from (5) contiguity low rank channel on the data stream to which only 3 O and Q 5 T were advanced, and (4) contiguity. Microprocessor 17 gives the adjustment pattern of a series of 32 symbol length of line 106 from FTFO stack 36 whose Opening operation in adjustment mode becomes possible to FIR filter 12 of a modulation part between adjustment modes. Time progresses (advances) and, as for time delay (delays), only 0.05 T carries out the skew of the two streams. CCU sets a modem as adjustment mode and makes the modulation part of a modem read the special adjustment pattern from FIFO stack 36 by operating adjustment mode switching arrangement 11 with the control signal of line 107 from control word register 31. According to necessary [ experimental ], he also follows a demodulation section, thru/or delay is received. If processing is completed, a modem sends out the status message that the coefficient was calculated to CCU. A modem is examined by setting a modem as normal operation and writing in a setting pattern, ordering that CCU establishes a loop bank to RFU, reads return data, and examines the validity of that data at this time. Adjustment mode is put into operation by setting up a control register bit with suitable CCU, and sending out the MOD RESET signal of line 54 to a modem. thereby -- it reconstructs from use to 2 of ll0M45 at use and 0- of IIAM, and reconstructs microprocessor 17 to use four of ROM 2 of use and RAM44. An adjustment mode algorithm is held to 2 of this ROM45, and 2 of RAM44 is provided with work memory storage at the time of calculation of a filter factor. - One algorithm calculates the contiguity channel characteristic. In order to determine a contiguity channel interface, this which must be able to transmit the modulation part of a modem on the frequency which removed 25 kHz from the received frequency is attained when CCU reads the status register of a modem. It is ordered the information in status Register 24 so that the frequency in a RFII receiver part may be changed into CCU depending on a modem. Microprocessor 17 performs an adjustment routine. # An A ready ready 1-Ching function is calculating a FIR filter factor by microprocessor 17. A modulation part is started in loopback mode and sends out the symbol sequence which changes. This sequence is transmitted to a demodulation section via RFU in the following five kinds of different modes. (1) A setup of AGC increases only 23 dB in regular mode, (2) progress timing modes, (3) delay timing modes and (4 and 5) a contiguity higher rank, the mode about a low rank channel, and the last two modes. A modulation part generates positive constant Limit symmetrical matrix A with 28 grades using the sample of an input waveform. 28-word vector V is generated from an input sample. Coefficient vector C is given by a following formula. C-A-'-V .................. (Formula 2) The algorithm which grows into calculation of B = A-' (given A) is used. According to a rounding error, since the value of B is not exact, much more exact C is calculated by " A repetitive method being. The 28th place of this calculation produces the complex FIR filter factor of a number. A modulation part is started in adjustment mode and transmits five same sequence pairs (pair of 5equences). Each pair comprises the following two sequences. (a) Q sequence of summer sequence of nine Null symbols, a '1" symbol and 22 Null symbols, and the Null symbol of nine mountains, a 'j' symbol and 22 Null symbols. "j" what kind of symbol may be sufficient as whose 11" is a symbol different 90 degrees from "1." The processing task of a demodulation section, It adjusts so that the signal peak in ill regular mode may be the greatest 50~70% (about the 4th and 5th modes, AGC increases only by 23 dB). (2) Read and memorize an input sample (each sequence throws away the first 32 samples and memorizes the following 64 samples). (3) The following processing is performed in building matrix A (28, 28) and regular mode (the 1st mode). A(T, J)-A(1, J)+sigmaX(4N-1)X (4 N-J) - (formula 3) -- this addition is performed about all the N which satisfies a following formula. O<=4N-1<64 and 0<=4N-J<64 ... (formula 4) The same processing is performed except for the paragraph acquired from N-8 not being added about % type % (the 2nd and 3rd modes). The following processing is performed in the 4th and 5th modes (transmission about the contiguity channel of a higher rank and a low rank). A(I, J)-A(1, J)+sigmaX(2N-1)X (2 N-J) - (formula 5) -- this addition is performed about all the N which satisfies a following formula. 0 <=2N-1<64 and 052N-J<54 ... (2 6) The processing task of the demodulation section of others in adjustment mode is as follows. <4 Generate vector V (1:28) from the first sample of a sequence pair. a I (V(I)) = X (32I) and = - (formula 7) here -- X -- the 1st (1) it is a sample of a sequence -- and To Q (V (1)) -X (32-1') ..-... C type 8 -- here -- X -- the 2nd (Q) it is a sample of a sequence -- and +51 Asking for coefficient vector C and this are performed by solving A X C-V-0 by asking for B which is a backlight of A first. According to a rounding error, B has the probability which is not exact. The following iteration method is used for the solution which asks for exact C. C,-BXV ............ (Formula 9) C*-+ s-C+a-b X B (A X Ca-V) = .. = -- predetermined value whose b is smallness from l here (formula 10).

[Brief Description of the Drawings]

the -- the [A / 1 / figure and ] -- whenB [ 1 ] figure is pasted together, it is a block diagram of the desirable embodiment of the modem of the present invention, and Drawing 2 is a figure showing a series of signals at the time of gray-code-izing the symbol of a bit stream -- Drawing 3 -- FIR digital of the modulation part of the above-mentioned modem. It is a block diagram of a filter and Drawing 4 is FIR digital [ of the modulation part of the above-mentioned modem ]. It is a figure showing the multiplex sample impulse response pattern of a filter, and Drawing 5 is a block diagram of the SIN/CO5IF generator of the demodulation section of the above-mentioned modem, and Drawing 6 is a figure showing the timing waveform of the control about operation of the above-mentioned modem which changes, timing, and a data signal. Explanations of letters or numerals of a main part 10 ... Fixed storage 11 ... Adjustment mode change device 12 [ 15 / ... Digital microprocessor 18 / ... FIFO stack / ... Mixer 16 ... RF amplifier 17 ] ... FIR digital filter 13 ... Digital analog converter 14 ... Zone filter 19 ... Analog digital converter 20 ... Amplifier 21 [ 23 ... Bus controller 24 ... Status register ] ... Mixer 22 ... Line 25 ... Link Q register 26 ... AGC register 27 ... RX frequency register 28 ... Delay register 29 [ ... Control device / 32 ... Delay register. ] ... The phase register 30 ... Right-angled phase Q register 31 34 [ 37 / ... Cell Sinal delay generator 41 / ... vcxo / ... Data latch 38 degreedegreedegree A part Timing 7 A and control signal generator 39 ... Transmitting clock delay device 40 ] ... Buffer control device 35 ... Reading / write-in decoder 36 ... FIFO stack Interfacing unit [ 45 / ... A buffer / attenuation machine device 48 / ... Buffer device / ... ROM46 ... ROM47 ] 42 ... Sample time generator 43 ... CO3/SIN IF signal generator 44 ... RAM 49 ... System timing apparatus applicant for a patent International Mobile MACHINES COVER REASSIN