Demand assignment method and system for a time division multiple access satellite communication network.

[Detailed Description of the Invention]

[Industrial Application] The present invention relates to a broad sense at satellite communication, and also specifically relates to improvement of the connection demand quota (demand assignment) method for a satellite communication circuit. [Description of the Prior Art] The usual time division multiple access (TDMA) satellite communication circuit is using many radio stations which receive the time multiplex composite signal of the burst including the abnormal-conditions information which communicates by transmitting the burst by which the time synchronization was carried out via Repeater of a satellite, and corresponds from Repeater. In TDMA operation, many ground stations relevant to a radio signal node (node) transmit the burst of a time concentration information signal by a share subcarrier cycle spectrum, are the subcarrier frequency spectrum to which the burst of the information signal was shifted, and receive it after repetition by satellite Repeater. An every place top office transmits the burst, and in order to receive a burst of itself, and the burst of other offices, a specific time slot is assigned into the continuity of a repetitive frame. All the bursts are interleaved in a satellite by the time organization which approached without overlapping. [Problem(s) to be Solved by the Invention] relative distribution of a connection demand [ in / on connection demand assignment and operation of conventional technology, and / the ground station signal node of versatility / length / of a quota slot ] -- therefore, it may change. As for the conventional connection demand quota technique, it is I or intermediary To have to take most time to change from the 1st channel assignment to channel assignment of the 2nd group. Excessive time required for the conventional connection demand quota technique which performs a shift during channel assignment makes high probability that new A call is blocked during the new rediscount reliance. The object of the present invention is to increase the efficiency of operation in the case of change of the channel assignment done all over a TDMA satellite communication circuit. Other objects of the present invention are to make into the minimum a possibility that new A call is blocked all over a TDMA satellite communication circuit. The object of further others of the present invention is to shorten the transition time under connection demand quota operation of a TDMA satellite communication network. [Means for Solving the Problem] The objects, such as this, are achieved by connection demand assignment by which the present invention was improved. In a time division multiple access satellite communication system, a standard office not only assigns channel capacity, but performs adjustment of a demand of capacity of all the ground stations. Adjustment is attained by a means by the side of a standard office for transmitting a restriction message, a block message, and a cancellation message to a ground station, and means by the side of a ground station which answers these messages and adjusts processing of an input service request. A restriction message is restricted to the number of channels demanded by a channel request message of the last to which the amount of the channel used was transmitted to a ground station, and it announces that the last channel assignment is not exceeded. A block message orders appearance (it prevents) which does not count the new connection demand on input ports, such as it, as an increase in a connection demand, but blocks it unconditionally to a ground station, and decreases concentration of a connection demand in a system effectively by this. When a channel demand decreases and a leeway is given in capacity as a result, a standard office cancels a block message told before, and cancels it by a message. As a result, a connection demand allocation method of the present invention decreases probability that give a more efficient device for carrying out rediscount reliance of the communication channel in a TDMA network, and new A call is blocked during the rediscount reliance. [Example] Time division multiple access (TDMA) means total bandwidth common use of the satellite transponder by two or the ground station beyond it on a time sharing basis. Although at least one transponder is included in a satellite, it is written as a satellite including a transponder below. Drawing 1 shows the relative location of ground stations 1 and 2 on the surface of earth 4 to geostationary satellite 5 which turns around about 36000-km orbit on the surface of earth 4, and standard office 3. An every place top office includes connection with the digital line and voice line which are inputted from the terrestrial source of a signal. Entrance cables, such as this, are connected to the digital dataport and voice port on a satellite communication controller (SCC), respectively. SCC is a communication switching system controlled by the computer which uses the digital transmission technique of a time division multiple access format. This format shown in Drawing 3 is an output to a burst modem. In a real time base, the burst modem coded the baseband signal received from a satellite communication controller, and has interfaced with the device of a radio frequency with the intermediate frequency. During reception, the burst modem decoded the signal received from an RF device, and has interfaced with SCC in base band frequency. The gate of the burst modem is done to ON and OFF by SCC during transmission. A burst modem has a low duty cycle, and it interleaves it with other ground stations on a time sharing basis by the same subcarrier frequency so that a burst may be in agreement with TDMA operational mode during the ON. As shown during the format of Drawing 3, the time in satellite 5 is divided into the 15 milliseconds (1260 channels) unit called a frame. In order that an every place top office may transmit the traffic burst by standard office 3 in satellite 5, one copy of a frame is assigned. To an every place top office, the time length assigned to an every place top office may change with time rather than is the same. The time length assigned to an every place top office is determined by the connection demand quota mechanism indicated by this specification. This mechanism determines the time length to which an every place top office is assigned into a frame in consideration of an every place top office and all the networks. As shown all over the 3rd figure, a frame comprises the activity ground station in a network from the fixed time interval assigned for transmission of the network control and synchronous information and track which reach 1 in a network thru/or other offices beyond it. A 15 mm (1260 channels) frame is divided into two portions, i.e., a control field, and the traffic field. The burst of the information from each of an every place top office is transmitted based on time division multiple access technique in each frame. Each burst comprises the unit of the information called the channel which comprises 512 2 Advance bit, respectively. The portion of the beginning of a frame is called a control field. The control field is 10.5 channels in length. A control field comprises a frame reference burst (FRB) and five transmission reference bursts (XRB). FRB comprises a total of three channels of 2.5 channel bursts and the guard time (GRD) of 1/2 channel, and is sent once by the standard office for every frame. This stores the quota information for 21 ground stations, and marks the start of each frame. FRB is used by SCC of an every place top office in order to maintain the synchronization of a frame. A transmission reference burst (XRB) is once transmitted by the every place top office to every super-frame (for example, 4 frame group x5 frame = 20 frames), as it has the length which added the guard time of 1/2 channel to an one-channel burst and was shown in Drawing 3. One specific position in a frame control field is assigned to the transmission reference burst of an every place top office. Each SCC in an every place top office uses the transmission reference burst, and holds the clock synchronizer of transmission. Each SCC uses the transmission reference burst similarly, and transmits the request of the demand for the transponder capacity of a satellite to a standard office. The direction of the flow of the information on demand 6 which calculates the channel capacity from ground station 2 of Drawing 1, and demand 7 which calculates the channel capacity from ground station 1 is shown. This demand is combined with TDMA format 8 in satellite 5, and it is transmitted to standard office 3. Drawing 2 illustrates the response which gives assignment during TDMA format 10 which shows the response of standard office 3, transmits Then and channel assignment 9 to satellite 5, and is transmitted to ground stations 1 and 2. With reference to the format of Drawing 3, the remaining portion after the control field of the frames of 1260 channels is the traffic field. The traffic field is constituted from an active every place top office in a transponder by the addressing Sent traffic burst to one. The length of a traffic burst is variable. The length and position are assigned by the standard office into a frame reference burst. A traffic burst is used in order to transmit traffic and signal information by a ground station. A transmission standard signal is sent all over the traffic field during initial transmission information capture, and the range is determined. The portion of the traffic field left behind after all the ground stations are assigned to a burst is called the non-assigning field. One frame group comprises five frames and has a 75-millisecond period. A frame group is a base of the timing in satellite 5 for transmitting burst assignment to all the ground stations. A frame group contains five frame reference bursts (FRB) including 105 burst assignment. A frame group contains the slot for 25 transmission reference bursts (XRB) similarly sent to a standard office from the ground station of 25, respectively. As shown in Drawing 3, a super-frame comprises five frame groups and has a time interval of 300 milliseconds. A super-frame is used as a hourly base for change of traffic burst assignment as a hourly base for a transmission reference burst. An every place top office transmits the transmission reference burst once for each super-frame of every. A standard office transmits the whole assignment repeated 4 times into a super-frame. New assignment becomes effective after the transmission on two super-inter-frame super-frame boundaries. Drawing 1 shows a TDMA satellite communication system including satellite 5, standard office 3, and two or more ground stations 1 and 2. It is shown that Drawing 5 has input ports 12 and 18 for inputting the asynchronous connection demand for voice transmission line 18 by which every place top offices 1 and 2 result from a ground network to satellite 5, or data-communications line 12. Plurality [ as opposed to every place top offices 1 and 2 based on the demand into which Drawing 3 is made by each of each ground station 1 and 2 in quest of channel capacity ] (N)_TTwo or more fewer channels N from the time sharing channel of Pieces_IA To TDMA format is shown. Drawing 5 shows the connection demand quota mechanism for ground stations 1 and 2. Digital port connection demand 12 is an input to point ON advance withdrawal (FIFO) stack 14, and has the input and output connection to connection advance (GO AHEAD) logical block 16. The output of logical block 16 is connected to channel demand logical device 28. Voice port connection demand 18 is an input to port request block logical device 20, the gate of the output is carried out by connection port arrangement object gate 24, and it progresses to channel demand logical device 28. Port cutting demand 22 is also inputted into connection port arrangement object gate 24. Channel demand logical device 28 calculates a channel demand based on a port demand. Drawing 5 shows transmitting block 34 which is a burst modem like Above similarly. The output of transmitting machine block 34 is connected to RF terminal unit 36, and Drawing 7 which transmits the channel demand calculated by channel demand logical device 28 with terminal unit 36 to satellite 5 shows the demand quota mechanism in standard SCC ground station 3. Frequency conversion of the channel demand from the demand quota mechanism in ground station SCC1 shown in Drawing 5 is carried out via satellite 5, and it is received by RF terminal 40 of Like standard SCC3 shown in Drawing 7. The channel demand from all of ground station SCC1 and 2 is sent via receiver block 42 in the 7th figure. Channel demand arrangement object 46 connected to the output of receiver 42 memorizes the new channel capacity quota demand from ground stations 1 and 2 belonging to a network. The present channel quota arrangement object 48 includes the present channel arrangement object for [ all the ] the ground station in a network. In this present channel quota arrangement object, the total capacity of a network is distributed in proportion to the demand track record of the past of a related office. As long as all the network demands are below total network capacity, the channel more than the past demand is assigned to each office. Therefore, the small change in traffic is immediately canceled by the office, without waiting for new channel assignment. Comparison machine 52 compares the new channel demand from an every place top office with its channel assignment of the present when it corresponds. If the new channel demand for a specific ground station is more than the present channel capacity, an output signal will be supplied to AND gate 56 from comparison machine 52, and AND gate 56 will start transmission of the restriction instructions by control logic device 54. In this case, restriction instructions are sent to all the ground stations 1 and 2 via satellite 5 with transmitting machine 44 and RF terminal 40. Restriction instructions are ordered to restrict to +one channel needed for the request message of the last transmitted to all the SCC1 and 2, however the number of channels which does not exceed the last channel assignment. A call of a sound and data may be connected within this restriction. When the channel demand of the next group from ground stations 1 and 2 is received by standard office 3, standard office 3 gets to know that this is expressing the maximum amount used. New channel assignment is attained at this time. A restriction message is the total channel capacity N._TIt is sent only when larger than the new demand of But channel capacity. This is determined by accumulator 50 holding the total value of the sum of a new channel demand. N this was remembered to be in register 58 among comparison machine 60_TIt is compared with a of value. N_TBut -- if larger than the sum of a new channel demand, an output will be sent to AND gate 56 and it will enable the signal from comparison machine 52 to reach transmission limit logical device 54. Drawing 5 shows ground station 1 connected to RF terminal 36 which receives the restriction instructions by which frequency modulation is carried out with satellite 5 from standard office 3, or receiver block 38 in two. Channel demand logical device 28 connected to receiver 38 determines the present assignment from the present quota register 26, and is connected with port request block logical device 20, Voice port connection demand 18 newer than the quantity of +one request message of the transmitted last in the case of many quantity is blocked. A sound and a data call may be connected within this restriction. When the next group of a channel demand is compiled by channel demand logical device 28 and sent to standard office 3 with transmitting machine 34, a standard office gets to know that this expresses the maximum present amount used. In Drawing 7, the demand quota mechanism in standard office 3 contains channel quota logical device 68 connected to new channel demand arrangement object 46. One copy (N) of the channel demand + excessive channel to which channel quota logical device 68 corresponds in proportion to the relative demand of a ground station in relation to all the channel demands of all the networks, respectively_TA new channel equal to thing x (relative demand of each ground station to the total channel demand in all the networks) which subtracted the sum of the channel demand, Or et al., is assigned to ground stations 1 and 2. New channel assignment is outputted to ground stations 1 and 2 via satellite 5 from channel quota logical device 68 via transmitting machine 44 and RF terminal unit 40. When all the sums of the channel demand for a network with new comparison machine 60 determine to be larger than the quantity in total network channel capacity in quantity, An enabling signal is sent to AND gate 62, and AND gate 62 starts transmission of a block message from transmitting block logical device 64 combining the demand from the arbitrary ground stations which calculate additional channel capacity. From logical device 64, a block message reaches transmitting machine 44, ranks next RF terminal unit 40, and is emitted towards all the ground stations 1 and 2 via satellite 5. A block message orders to refuse the voice call introduced to offices 1 and 2 of all the networks. Digital A call introduced is made queuing by FIFO stack 14 in every place top office SCC1 and 2. Thus, use of capacity is attained at the time of the present sound and digital Be called out. In Drawing 5, a block message is received by receiver 38 via RF terminal unit 36, and is turned to port request block logical device 20 here. In relation to connected port arrangement object logical device 24, logical device 20 blocks all the new voice port demands, and makes new digital A call queuing altogether from digital port terminal area 12 in FIFO stack 14. While the block instructions are operating in every place top office SCC1 and 2, channel instruction logical device 28 generates a new channel demand to standard office 3 via transmitting machine 34 periodically. When a present sound and digital A call go out, use of capacity is attained. In Drawing 7, the demand quota mechanism in standard SCC3 has accumulator 50, and totals continuously the new channel demand from ground station SCC1 and 2. Channel quota logical devices 68 are all the sums N of a new channel demand from all the ground stations._IThe total channel capacity N of The network_TIt is new channel N as a demand to the ground station which is alike, and needs additional channel capacity when not reaching._ITo. Standard office 3 transmits new channel assignment to ground stations 1 and 2 via transmitter 44, RF terminal unit 40, and satellite 5. In order to withdraw the effect of a block message proper, a specific cancellation message may be sent. The voice activity ratio (A) used when Drawing 6 determines the channel demand for a ground station_Vthe logical device of ground stations 1 and 2 for calculating -- a detailed portion is shown further. SCC1 of all the users and 2 transmit the present channel demand to standard SCC3 periodically. Drawing 9 shows the outline of this process. Connected voice off-Hook is an independent variable used into the table lookup roughly shown in 84 of Drawing 9. This table produces the number of the channels needed for supporting this voice call. This table shows the relation of channel needed by method similar to Like graph shown in Drawing 11 versus voice off-Hook. The voice activity ratio (A) calculated in ground station SCC or 2 by logical device 30 by which the specific table used was shown in Drawing 5_VIt is determined. Drawing 6 has accumulator 70 which has the number of the voice ports connected to per frame as an input. Supposing comparison machine 76 has the sum larger than a constant from accumulator 70 as compared with the constant memorized in register 74 in the sum in accumulator 70, Division machine logical device 78 is enabled and division of the number of the blocks of the sound which occurred per frame is done by a speaker's number of sums to which per frame was connected. This quotient is a voice activity ratio (A)._VIt is used for choosing the entry of a specific table into table lookup 84 which expresses a size and produces the actual number needed, and the real number of the demanded channel is taught. This A_VA value is the quantity of the demand sent to standard office 3 by ground station SCC1 or 2. [Explanation of operation] Next, operation of the present invention is explained. Managing network channel capacity appropriately has a function of the system of the present invention. A channel demand is calculated by SCC of the user in a network, and is transmitted to standard SCC via a XRB channel. After calculating channel assignment based on a demand of this etc., as assignment was shown in Drawing 4, it is made via a FRB channel. Network channel capacity (N)_TIt is assumed that they are fixed numbers. Generally, the amount of whole picture of a network is distributed to a user's office. The demand of all the networks exceeds the capacity of a network. That is, when exceeding slightly, supposing it is approved, a transponder and a channel pool will be used. Supposing a pool is called, use of the channel of a large number from a pool will be temporarily enabled to this network. As shown in Drawing 8, maintenance of audio quality, i.e., the restriction to a certain level of the freeze which the user of SCC receives, is performed by user SCC. User SCC restricts the number of the voice calls connected to this appearance as what channel assignment was given, and it must be carried out as [ break / the standard of a freeze ]. This thing is performed by channel demand technique. The channel demand (C) for the sound to which user SCC was connected similarly_RVThe channel (C) needed for connected digital A call_RDAnd demand capacity (C) to digital A call made into the oldest queuing_DQIt calculates. Management of a quality of service is made by standard SCC3. The management must distribute channel capacity among user SCC 1 and 2 so that the probability of A call blocking may be cotton intermediary regularity in a network. This is performed by channel distribution technique. Standard SCC3 has the instructions which make the voice call which acts as all the user SCC in a network, and introduces it block. These instructions are used when collecting channels for for example, a digital data call. Periodically, all the user SCC1 and 2 send the channel demand of the present, such as it, to standard SCC3. Drawing 9 shows the outline of this process. Connected voice off-Hook produces the channel needed in order to act as Key of the table lookup and to support a voice call. This table is listing channel needed versus voice off-Hook. The voice activity ratio (A) by which the specific front entry used is calculated in this SCC_VIt is determined. the maximum freeze level finally expected the group of the table in SCC in this SCC -- therefore, it is chosen. A digital data request is displayed separately. The dataport (C) connected_RDor [ that new digital A call is connected to the receiving channel demand when the requirements for an audio channel change remarkably ] -- or it is calculated when intercepted. Before digital A call is connected similarly, it is calculated whether this A call may be connected or in SCC1, it must be made queuing. The number of the channels used in order to support the group of digital connection is determined as following. The 1st port is divided into two categories, i.e., a high speed, and a low speed. In the case of this high-speed port, a channel demand is determined from table lookup 86. A front entry usually has a port equal to the maximum number of the channel which can be sent in one frame. Assigning a smaller number of channels to one port can permit a data freeze, and when the activity factor of the port is known, application of it will be attained in the future. Table 86 contains this possibility. In the case of a low-speed degree port, a channel demand is a function of port speed and an audio channel demand. For example, since SCC1 is a voice call, when it is using five channels, in order to support a 10-19.2k BPS dataport, a simulation shows needing three channels. However, what is necessary is just to add only one channel to supporting a 10-19.2k BPS dataport, supposing 25 channels are used for a voice call. As shown in Drawing 10, sufficient capacity can be given now to new A call by restricting a voice call. Off-Hook of the maximum number is determined by Table 84 to the given channel assignment. If the off-Hook + present connected new off-Hook exceeds the maximum of all the off-Hook, the new data call by which new A call is blocked by 88 must be restricted so that the capacity which can be used may not be exceeded similarly. However, when the sum of the capacity which was connected and was made the procession exceeds restriction of the greatest SCC, the data call which is not connectable is queuing-ized by stack 14 of Drawing 5, and a new data call is blocked in this case. A queuing data call (C) with an old instruction message to standard office 3_QDThe capacity demanded by receiving and the display between the arrival time of the oldest Queue call about when the network was blocked are included. Generally, when use of channel capacity is attained, the data call made into queuing in SCC1 is connected in order of FIFO in 14. Audio channel demand Many of capacity of the channel in a network is used for voice traffic. Efficient voice operation is indispensable to the efficiency of a good network. The grade of the efficiency for voice operation is given with the voice activity compression (VAC) value acquired using voice compression technique. A VAC value is a voice activity ratio (A)._VIt is a function. Some factors, for example, a voice activity threshold, the tactical air weapon control system part overhang applied, circuit noise, the background noise of an office, the model of business, the local voice characteristic, and a factor like use of an analog modem are ratios (A)._VIt is affected. It is dynamic (A) in order to attain the maximum degree of VAC good in SCC._VSystem 30 of Drawing 6 to measure is used. This determines the ratio to the number of the voice ports where per frame was connected with the channel by which per frame was generated for transmission. This ratio (A)_VIt is used for choosing a suitable curve from the group of the Like curve shown in Drawing 11. Drawing 11 associates off-Hook of the channel needed and a voice port. For the object of explanation, Drawing 11 assumes the phrase out (freeze) (FO) percentage which is 0.001% thru/or 1%, and the channel opposite needed in the voice port (N) which is connected in the case of A= 0.4 and A= 0.3 is shown. The formula used for generating this curve is given as following. several [ of several N= Heisi port (speech generator) of a block of the speech which occurred during X= 1 calculation of freezing out percentage ] -- several A of the channel in which C= use is possible_V= Activity Beatty Facta (average) number [ of the blocks in which the block of FO%= freezing out was generated several/] x100 -- therefore<img file="JPS6324331B2_D0001.tif" />The curve showing the probability of (the random independent speech generator having been assumed) or the Like freezing out shown in Drawing 13 is used. Versatility (A)_VA curvilinear group is drawn for every specific probability of freezing out. The VAC profit curvilinear group of Use SCC can be concretely shown for the same mechanism like the above. It is an activity (A) about effective use of the VAC profit curvilinear group in the 11th figure._VCalculation is needed. A_VOne ratio is formed in order to calculate. Molecules are a number of a block of a speech of sums which occurred per frame of time T. Denominators are a number of a speaker of sums connected to per frame during time T. Namely, A_V= sigma_T(Several/frame of the generated speaker) / sigma_T((Several/frame of the connected speaker) A)_VSo that the accuracy of an estimate is a function of the sample number considered, namely, the number of samples is large (A)_VAn estimate becomes more exact. In order to maintain the accuracy in SCC of arbitrary scales uniformly (A)_VIt is calculated only once. The value of a denominator becomes larger than the threshold in which Set is possible. As opposed to the given correctness (A)_VThe time for presuming is T4A._V(1-A_V)²xL/Nsigma_A²It comes out. L is length which is average conversation and which continues one (tactical air weapon control system part) here,_A²Is (A)_VIn distribution, N is the number of speakers. the inside of T -- the sums of the number of speakers are (T) x(N) x1/0.015 per frame. This It is assumed that it is that in which per second 1 / 0.015 frame exists by This. therefore sigma_T(Several/frame of a speaker) =4A_V(1-A_V)²xL/0.015sigma_A²It becomes. A_V= 0.3,_A= It is sigma when it assumes that they are 0.01, and L= 1 second._T(Several/frame of a speaker) =4x10⁵It becomes. The threshold (2) in which this Set is possible²⁰&gt;10⁶Since it expresses, it is appropriate to use the number of 20 A bit. The network channel distribution method Managing the capacity of the channel of a network appropriately has a function of this method. Generally, the capacity of a network is assigned in order to satisfy the necessity for the office in a network. Standard office 3 receives the demand of the channel for all the SCC1 in a network, and 2. The channel demand (C) for a sound_RVThe channel demand (C) for data_RDAnd A call (C) of the data made the oldest procession_QDIt appears in a transmission reference burst (XRB) from each user's offices 1 and 2 between the receiving channel demand and the relative arrival time. (C_RVThe actual demand for A call of an on-going sound is shown. (C_RDThe channel needed in order to support the connected data call is specified. Supposing network capacity is sufficient size to total of a demand, all the demands will be satisfied, and it is remainder (C)._RVIt is distributed as a function. Drawing 14 shows the stage in a process. The following expression of relations is established in relation to Drawing 14. (1) sigma demand == NC_RV+ = NC_RD+ = NC_QD(2) Required capacity [ of a pool ] =N_T- sigma demand &lt;P_TIt is here and is P._TIt is a threshold (the number of channels) used for making access to a Is pool start. (3) Usable quantity [ of a pool ] =(amount of pool used approved) -(part for the increase which can use pool) -= NC_RD+ = NC_QDThe total amount of the loan from a pool (4) Necessary quantity == returned to a pool NC_RD+ = NC_QDThe total capacity + of &lt; loan (N)_T- sigma demand &gt;P_R) It is here and is P._RIt is a threshold (the number of channels) used in order to start the return of a channel to a Is pool. (5) Each excessive capacity = quota capacity &gt;K in the excessive capacity in certain SCC / its SCC -- here, K is a constant between 0 and 1. N= network N_T= Total network capacity - = and logic + = or logic A user channel demand is received (stage 100), and the capacity of a pool is not needed (stage 102), and a block (stage 104) and restriction (stage 106) assume that it is OFF (released). arbitrary digital data calls are made into queuing -- Listen (stage 108) -- or [ or / exceeding assignment of a user's present ] -- or the equal (stage 110) necessity of rediscount reliance being needed if it becomes, and using excessive capacity is imminent (stage 112). Rediscount reliance assumes that it is what is needed for A call made into queuing. In stage 110, it is a voice demand (C)._RVPeace and the sum (C) of a demand of data_RD+C_QDThe sum total is network channel capacity (N)._TThe test of whether to exceed is made. If yes becomes, a block (stage 114) will be Set(ed), and it orders for this to refuse A call of the sound introduced to offices 1 and 2 of all the networks. Introductory digital A call is made queuing by 14 in SCC1 and 2. When a present sound and digital A call are lost, use of capacity is attained. The channel request message from 2 to partial SCC1 and standard office SCC3 via XRB shows reduction of channel availability. Since the block (stage 114) is ON, a channel demand is received at each time (stage 104), and this sum is N._TIt is compared (stage 116). Peace is N._TIt is smaller, or new assignment is calculated and (stage 118) transmitted when equal. Subsequently, blocking is canceled (stage 120). This operation arises, when the capacity of a network is insufficient although for example, the digital data call was generated, and it cannot respond this to it. If it assumes that restriction (stage 106) and a block (stage 104) are OFF, rediscount reliance will be needed and an output will be taken out to the N side of stage 112. Several +one of the channels demanded in the newest request message to which restriction was sent here (stage 122) and the amount of the channel used was transmitted to all the SCC1 and 2 (1+C)_RV+C_RDHowever, it is restricted so that the last channel allotment may not be exceeded. A sound and a data call may be connected into this restriction. When the group of the next channel demand is received by standard office 3, standard office 3 gets to know that this expresses the maximum amount used. It That and all demands of stage 116 are N._TIt is [ whether it is the following and ] N._TIf it is alike and an equal thing is shown, new assignment will be calculated (stage 118) and assignment will actually be performed. This operation arises, when rediscount reliance is needed for satisfying the demand in which a specific user increases, although the capacity of a network exceeds all the demands. however -- supposing an output becomes in stage 116 in YES -- excessive capacity -- a I used it user -- Oh -- it becomes things. Then, a block (prevention) is Set(ed) (stage 124). A block and the restriction should be instructions of a network, and when used, notice them about being applied to all the SCC 1, 2, and 3 in a network. When the necessity for rediscount reliance is shown by stage 110, excessive capacity must be able to be used partly (stage 126), and rediscount reliance will not be made if it cannot use. This operation is made as [ prevent / excessive rediscount reliance ], when the demand of the sound under too heavy loading has variation. this excessive rediscount reliance may arise all over one a user's specific SCC or network (for example, Only from a pool -- it is only borrowing) -- supposing there is no excess, rediscount reliance should do -- there is nothing. New channel quota Set (Ca)_iSCC_iIt is alike, and it receives, and the following rule is used when calculated.<img file="JPS6324331B2_D0002.tif" />E is the capacity of an excessive network here. E=N_T-_o=ⁱ⁼¹C_RV+_o=ⁱ⁼¹C_RDThus, the capacity of an excessive channel is distributed to a user's office. Non-line type distribution makes quality of service equivalent, as probability of the block was made equivalent through the network, therefore it was shown in Drawing 8. The actual embodiment of the illustrated square root function can take the form of a table lookup. When the transponder channel pool network is approved by the electrical overload, standard office 3 can borrow the channel for a network from a transponder pool. As shown in Drawing 14, stage 102 inspects the load of a network. An exceeded part (N) to the total capacity of a network_T- The total demand is a pool access threshold (P)._TA pool can be used if small. If use of a pool is below the amount of whole picture for which the amount of whole picture which use of the pool is approved, can use the capacity of a pool, or it is going to borrow is needed to digital data, it is possible. When the capacity of a pool is used, this capacity is stage 127, and it is N._TIt is alike and is added. If the capacity of a pool is ending with borrowing, the check for getting to know whether return of capacity is required will be performed in stage 130. An overnetwork is a return access threshold (P)._RIf it is large or digital data volume is smaller than borrowed capacity, capacity will be returned to a pool. Capacity is N when pool capacity is returned._TIt is subtracted in Or stages 132. The queuing ratio of digital A call Like Above, if audio A call, and a different intermediary and digital A call must have been connected in SCC, this is made into queuing into FIFO14. This section explains a queuing system still in detail in relation to Drawings 5 and 15. A ground station SCC1 or 2: (1) FIFO queuing 14 which capacity cannot be locally used in stage 154 of Drawing 15, or makes a data call (restriction of SCC is not exceeded) queuing when a block is ON in stage 152 exists in each SCC 1, 2, and 3. (2) In stage 154, capacity can be used locally, and if a block is not ON in stage 152, A call of data will be connected by 156 always, when possible. (3) A block prevents connection of arbitrary A call except for the case of the following conditions. Conditions: Audio A call is refused and the digital data call is made into queuing. (4) If standard office 3 increased only the quantity needed for satisfying demand 14' made into queuing least recently in capacity assignment of SCC1 or 2, This A call is connected, and A call made into queuing least recently next will be promoted to oldest position 14' (supposing it exists). The message of a demand of the next sent by SCC1 shows the relative time of attainment of the demand of capacity made into this oldest "new" queuing, and the shown demand reflecting connected A call. It makes it possible to advance the data call of each queuing in specific SCC1 and 2, standard office 3 holding [ above-mentioned may be carried out also when a block is ON, and ] blocking of audio A call especially in SCC1 and 2. This operation is required to observe a point ON advance withdrawal service principle when giving its service to the digital data call made into queuing. (5) Drawing 15 shows overall operation in case a data call demand reaches by ground stations SCC1 and SCC2. Inspection 150 is conducted in order to see arbitrary A call whether first kept waiting in queuing. If it becomes so, all the subsequent data calls will be made into queuing. Similarly, A call will be made into queuing if a block is ON in 152. A call will be made into queuing if capacity is not locally usable in 154. This queuing is FIFO14. This queuing is inspected by the deadline in quest of Thank you in 160, and Thank you for calling is removed by the deadline. The demand of the capacity of A call in the oldest position will be a request message (C), if it exists._DQIt appears in inside. If a block is not ON (stage 152), use of capacity will be attained in stage 154 (stage 154), and A call made into queuing will be connected in order of FIFO. B standard SCC3: Rediscount reliance is needed, when an entry shows A call of the data made into queuing and appears. When a network is an electrical overload, digital A call is made into queuing in some SCC. When a block is caused, standard office 3 satisfies all the demands to the group of the data call made into queuing least recently, and tries as like. This thing is performed when stage 116 of Drawing 14 has an output of NO. NO output produces generating of the new assignment which gives the capacity of sufficient channel for all the ground station SCC1 and 2 to connect release (stage 120) of a block, and A call of the data made into the oldest queuing (stage 118). If additional A call is made into queuing in some ground stations SCC1 and SCC2 (stage 108), a block is caused again (stage 114) and a procedure is repeated. This procedure has the tendency to hold connection of A call of the digital data in a network in order of FIFO. In short, standard office 3 gives its service to the group of a digital data call. Standard office 3 is served for the group of A call of the data made into the oldest queuing in the FIFO order shown by between each arrival time shown in the request message from SCC1 and 2. In order to avoid that the address end of A call is completed while the dispatch end is still made into queuing, standard office 3 is not satisfied with between them of the demand capacity of which address connection, and dispatch connection equal [ attainment time ] or early is left behind to a queuing state in other SCC1 and 2. Signaling message conditions over C digital data call Facial expression: Some Full duplex call assume that it is occurred among SCC in a network. According to the usual signal protocol, each demand makes a sequence and reaches standard office SCC3 so that capacity may be assigned to one person of each conversation and may not be assigned to the others. since [ therefore, ] the capacity for which one person is needed cannot be obtained when it exists, in order that capacity may complete a certain thing of Full duplex call, such as this, -- which -- although -- it is not completed. The solution over this problem is preparing a signaling message protocol to high-speed digital A call by which a signal is carried out to Call request which called SCC produces in an addresser's SCC at the time of approximately said. If it carries out like this, both demands for channel capacity will arrive at standard office 3 at the time of approximately said. Standard office 3 is served for the group of a demand, and since the probability in the same group of both channel demand to a specific data call is high therefore, the capacity needed is received simultaneously. [Effect of the Invention] The connection demand quota method of the present invention improves the efficiency of the rediscount reliance of the communication channel in a TDMA network, and lessens a possibility that new A call may be blocked during the rediscount reliance.

[Brief Description of the Drawings]

Drawing 1 is a figure showing the 1st phase for demand assignment in case the relative location and ground station of a satellite relevant to the surface of a standard office, a ground station, and the earth send a demand of that etc. to a standard office, Drawing 2 is the 2nd schematic diagram of the ground station shown in Drawing 1 in case a standard office sends assignment of a channel to a ground station, Drawing 3 is a figure showing the super-frame format for a TDMA network, Drawing 4 is a schematic diagram of the flow of the information for a channel demand and channel assignment, It is a logical block figure of machinery for Drawing 5 to calculate the functional block diagram of the demand quota mechanism for a ground station, and for Drawing 6 calculate the probability of the voice activity in a ground station, It is a functional block diagram showing the operation which sets Drawing 7 to the functional block diagram of the quota mechanism of the demand for a standard office, sets Drawing 8 to a standard office and a ground station, and is carried out, Drawing 9 is a functional block diagram of the mechanism for calculating the demand of the capacity in a ground station, The sound in a ground station calls and Drawing 10 is [ the functional block diagram of a limiting mechanism and Drawing 11 ] in the function of a voice port to the probability of various voice activities in a ground station, The graph which showed the number of the channels needed, the figure showing the number of blocks of the conversation frozen in a frame with typical Drawing 12, and Drawing 13 receive various values of the probability frozen, The flow chart of channel distribution operation of a network and Drawing 15 of a number of several pair speaker of a channel of graphs needed and Drawing 14 are flow charts of operation of a ground station. 1,2 ...... A ground station, 3 ...... A standard office, 4 ...... The earth, 5 ...... A satellite, 14 ...... A FIFO stack, 16 ...... A connection advance logical device, 18 ...... a voice port connection demand and 20 ...... a port request block logical device and 22 ...... a port cutting demand and 24 ...... a connection port arrangement object and 26 ...... the present quota register and 28 ...... the logical device of a channel demand, and 30 ...... A_VA computational logic device, 32 [ ...... Receiving set. ] ...... A front demand register, 34 ...... A transmitting machine, 36 ...... RF terminal unit, 38