Apparatus and method for channel coding and multiplexing in cdma communication system

ES 2 269 880 T3

DESCRIPTION

Apparatus and method for channel coding and multiplexing in a CDMA communication system

The present invention relates generally to an apparatus, and a method, of channel communication in a mobile communication system, and in particular to an apparatus, and a method, of channel multiplexing and coding, in which multiple frames of transport channel are converted into multiple physical channel frames.

A conventional CDMA (Code Division Multiple Access) mobile communication system primarily provides a voice service. However, the future CDMA mobile communication system will support the IMT2000 standard, which can provide high-speed data service as well as voice service. More specifically, the IMT-2000 standard can provide a high-quality voice service, a high-quality moving image service, an Internet search service, and so on. This future CDMA communication system will consist of a downlink to transmit data a station from a base station to a mobile station, and a downlink to transmit data from the mobile station to the base station.

Thus, it will be desirable for the future CDMA communication system to provide various communication services such as simultaneous voice and data communications. However, the details for the simultaneous implementation of voice and data communications have yet to be specified.

3GPP Technical Specification TS 25.212, Multiplexing and channel coding (FDD), Working Group 1, Version 1.0.0,1999-04, describes the characteristics of the layer while multiplexing a channel coding in FDD mode of a UTRAN. In detail, it describes a data flow from, or to, the MAC and higher layers (transport block / transport block configuration), which is encoded and decrypted to offer transport services, with a radio transmission link. A channel coding scheme is a combination of error detection, error correction, rate adaptation, interleaving, and mapping of the transport channel over, or subdividing from, physical channels.

Therefore, the object of the present invention is to provide an improved channel receiving device for reversing the segmentation of a received serial data frame to a plurality of transport channel frames for a CDMA communication system.

This objective is achieved by the present invention, and in particular by the subject matter of the independent claim. Preferred embodiments are the subject of the dependent claims.

It is an aspect of the present invention to provide a channel coding and multiplexing apparatus, in which transport channel frame data is segmented into a plurality of radio frames, in a transmission device of a CDMA communication system. .

It is also an aspect of the present invention to provide a channel multiplexing and coding apparatus, in which each of the data frames of a plurality of transport channels is segmented into radio frames, and the radio frames segmented they are multiplexed, to form a serial data frame, in each radio frame transmission time interval (TTI), in a transmission device of a CDMA communication system.

Another spectrum of the present invention is to provide a channel coding and multiplexing apparatus, in which each of the data frames, of a plurality of transport channels, is segmented into radio frames, the radio frames are multiplexed to forming a serial data frame, in each radio frame TTI, and the serial data frame is segmented into a plurality of physical channel frames, for transmitting the physical channel frames over a plurality of physical channels, in a transmitting device of a CDMA communication system.

Yet another aspect of the present invention is to provide a channel multiplexing and coding apparatus, in which padding bits are added to channel frame data, and segmented into radio frames, in a channel transmission device. a CDMA communication system.

Yet another aspect of the present invention is to provide a channel multiplexing and encoding apparatus, in which the received physical radio frames are demultiplexed to form a plurality of radio frames, and the radio frames are subjected to segmentation inversion. , to form a transport channel frame in a channel receiving device, in a CDMA communication system.

Yet another aspect of the present invention is to provide a channel multiplexing and encoding apparatus, in which data frames received via multi-code physical channels are subjected to segmentation inversion to form a data frame. in series, and are demultiplexed to form radio frames of each of the transport channels, in a device of a CDMA communication system.

To achieve the above aspects, a channel coding and multiplexing apparatus in a CDMA communication system has as many frame adapters as there are transport channels, and a multiplexer. Each radio frame adapter has a radio frame segmentation device, and segments a transport channel frame,

ES 2 269 880 T3 that can have a different transmission time slot, with respect to the transmission time slots of other transport channel frames, on other transport channels, to form radio frames, and the multiplexer multiplexes the radio frames to a serial data frame.

The foregoing and other objectives, features, and advantages of the present invention will become more apparent from the following detailed description, when taken in conjunction with the accompanying drawings, in which:

Figure 1 is a block diagram of one embodiment of an uplink channel transmission device;

Figure 2 is a block diagram of one embodiment of a downlink channel transmission device;

Figure 3 is a view illustrating the operation of the channel transmission devices shown in Figures 1 and 2;

Figure 4 is a block diagram of one embodiment of a channel receiving device;

Figure 5 is a flow chart, illustrating a radio frame generation procedure using padding bits;

Figure 6 is a flow chart, illustrating a radio frame generation procedure without using filler bits;

Figure 7 is a flow chart, illustrating one embodiment of a radio frame multiplexing procedure; and FIG. 8 is a flow chart, illustrating one embodiment of a physical channel frame generation procedure.

Next, preferred embodiments of the present invention will be described with reference to the accompanying drawings. In the following description, well-known functions or constructions are not described in detail, as they would obscure the invention in unnecessary detail.

The segmentation, multiplexing, and physical channel segmentation, of radio frames, for channel coding and multiplexing, in a channel communication device of a CDMA communication system is defined in detail. That is, radio frame segmentation, radio frame multiplexing, and radio frame segmentation multiplexed into physical channel frames, which are not provided by the 3GPP Technical Specification of Multiplexing and Channel Coding, TS 25.212, Version 1.0.0, 1999.05.05, will be defined in sufficient detail to deal with bit-based operations. As mentioned above, the 3GPP Technical specification of Multiplexing and Channel Coding, TS 25.212, version 1.0.0, 1999.05.05, published by 3GPP Organizational Partners, can be considered as an additional source for channel multiplexing and coding.

Before describing the present invention, terms that are used herein will be defined. "Transport channel frame or input data frame": a data frame applied to the input of a radio frame adapter, from a channel encoder; "Radio frame": a data frame formed by segmenting the input transport channel frame, and the size of the radio frame is a function of the TTI of the transport channel frame and the TTI of the radio frame, as explained above. A transport channel frame can be transmitted at a different data rate, for a different transmission time interval (TTI).

The following description is made, with the appreciation that particular details, such as a radio frame TTI and the insertion position of a stuffing bit, are provided by way of example, for the understanding of the present invention. Therefore, it is clear to those skilled in the art that the present invention can be easily implemented without the details, or with the details being modified.

A description will now be made of the structures and operations of the 3GPP uplink and downlink channel coding and multiplexing apparatuses, including from first interleaving devices to second interleaving devices, according to an embodiment of the present invention.

Figures 1 and 2 are block diagrams of the uplink and downlink channel transmission devices, respectively, in accordance with one embodiment of the present invention. The receiving devices, for receiving information from the channel transmitting devices, have the inverse configurations of their counterparts. Figure 3 is a view mentioned to describe the operations of the channel transmission devices shown in Figures 1 and 2.

In accordance with the embodiment of the present invention, data frames received via at least two transport channels may have different TTIs, and different data rates. The radio frame adapters 101, 102, ... 10N (that is, "101 to 10N") receive the data frames of the corresponding radio channels.

ES 2 269 880 T3 transport, segment the received data frames into data of a size that is a function of the TTI of the transport channel frame and the radio frame TTIs (i.e. radio frames), and output from sequentially form the segmented radio frames (in reference numeral notation, the "N" is used at all times to indicate an indefinite number of respective components). Each of the 101 to 10N frame adapters includes an interleaving device to compensate for fading, a radio frame segmentation device, to segment a transport channel frame interleaved into radio frames, and a rate adapter to control the data rate of radio frames, by selectively removing / repeating certain parts of the radio takes. In the case where the bit number of a transport channel frame is not a multiple of a radio frame length, a corresponding radio adapter inserts a filler bit into the transport channel frame, which is performed on its radio frame segmentation device, by way of example in the embodiment of the present invention.

A multiplexer 200 sequentially multiplexes radio frames, received sequentially from radio frame adapters 101 to 10N, to a serial data stream.

In the case of multiple code transmission, a physical channel segmentation device 300 segments the serial data stream, received from multiplexing device 200, into as many data frames as the number of physical channels, using at least two codes, and transfers the data frames to the corresponding physical channels, so that the serial data frames can be transmitted over the physical channels.

In the case of a single code transmission, the physical channel segmentation device 300 does not need to segment the serial data stream, but rather transmit the serial data stream over a physical channel.

With reference to Figures 1 and 3, the reference number 100 denotes the entire block of coding and multiplexing chains, which have radio frame adapters 101 to 10N, to receive N encoded data, which can have different qualities of service ( QoS), in parallel. In other words, the data streams applied to the radio frame adapters 101a 10N, from the MAC layers and above (transport block / transport block configuration), may have different QoS. Specifically, the transport channel frames can have different data rates and different TTIs, and each radio frame adapter receives frame data, from a corresponding channel encoder. The same encoder delivers frame data of the same QoS, during each service. However, during another service the QoS of the same encoder may change to another QoS. Therefore, data of different QoS can be applied to the radio frame adapters 101 to 10N, but each radio frame adapter receives frame data of the same QoS during each individual service.

Each radio frame adapter receives encoded frame data, which has a different data frame size, and a different frame transmission period, according to its QoS from the corresponding channel encoder. QoS is determined by voice, data, images. Therefore, the data rate and TTI of frame data depend on its QoS. In carrying out the present invention, the data frames are assumed to have TTIs of 10, 20, 40, or 80 msec. According to this type of service, the input encoded data may have a different data rate and a different TTI. In other words, the frames on each channel have unique TTIs and data rates. In the case where one channel data is to be transmitted, the encoded data generated from a channel encoder is processed, and in the case where two channel data are to be transmitted, the generated data is processed at starting from two corresponding channel encoders.

Each of the first interleaving devices 11-11N essentially interleaves a transport channel frame, received from a corresponding channel encoder. Here, a transport frame received from each channel encoder may have a different TTI and a different data rate.

As shown in Figure 1, radio frames are referred to as RF, and are indexed as follows: RFy, where i = transport channel index, and j = radio frame index, for a transport channel side , and RF, refers to all radio frames on the ith transport channel (for example, RF_1i2 means a second radio frame on a first transport channel, and RF₁ refers to all radio frames on the first transport channel). Radio frame segmentation devices 121 to 12N segment radio frames LFi to LF_n, received from the first interleaving devices 111a 11N, respectively, in RF radio frames₁ to RF_n, respectively, as indicated by reference numeral 301 in Figure 3 and Figure 1, and deliver the RF radio frames₁ to RF_n sequentially, in the order of segmentation. In embodiments of the present invention, T refers to the number of radio frames in a transport channel i, where i = transport channel index (for example, T1 is equal to the number of radio frames in the first channel of transport). Here, the LF transport channel frames₁ to LF_N they can have different TTIs, and different data rates according to their channels. The radio frame TTI is assumed to be 10 ms, in the embodiment of the present invention. Thus, each of the RF radio frames₁ to RF_n, contains at most the data of a 10 ms frame duration, of the incoming transport channel frame. In this case, if a radio frame segmentation device receives a transport channel frame of an 80 ms TTI, it sequentially segments the 80 ms data frame into eight radio frames and sequentially delivers the data. radio frames. A radio frame adapter, which receives a transport channel frame of a 40 ms TTI, segments the 40 ms data frame sequentially, into four radio frames. Similarly, a radio frame adapter that receives a transport channel frame of a 20 ms TTI, segments the 20 ms data frame, sequentially into two radio frames. A 10 ms data frame has the same duration as the radio frame TTI, and is therefore delivered without segmentation.

ES 2 269 880 T3

The length in bits of a transport channel frame may not be an integer multiple of the length in bits of the radio frame. In this case, it is preferable to insert a filler bit into the transport channel frame, to make the bit length of the transport channel frame as long as a multiple of the radio frame bit length . That is, if L¡ / T¡ (L¡: the length of an input transport channel frame, in the i-th transport channel and, in certain embodiments of the present invention, T¡ = TTI for the i -th transport channel / 10 msec) is not an integer, a padding bit is inserted. The stuffing bit is processed prior to radio frame segmentation, to maintain a constant radio frame length, during a transmission period. Transmission of all transport channel frames is easily controlled by keeping a radio frame length constant within the TTI of the transport channel frames. When a transport channel frame has a maximum TTI of 80 ms, a maximum of seven padding bits can be used. The decrease in transmission efficiency that appears from an increase in the frame rate of the totality of the data, caused by the addition of these padding bits, is negligibly small. Radio frame segmentation devices 121 to 12N sequentially segment incoming transport channel frames into 10 ms RF radio frames₁to RF_n, as indicated by reference numeral 302, in Figure 3. Rate adapters 131 to 13N adjust the data rates of RF radio frames₁ to RF_N, received from radio frame segmentation devices 121 to 12N, respectively, and deliver KF radio frames₁ to KF_N, respectively. K¡ refers to the length of the respective frames KF¡.

The above radio frame adapters 101 to 10N, receive corresponding transport channel frames in parallel, verify the transport channel frame sizes, segment the transport channel frames into radio frames, and deliver the frames in parallel. radio. Multiplexer 200 multiplexes radio frames KF1 to KF_n, received from rate adapters 131a 13N, to a serial data stream of size P, as indicated by reference numeral 303 in FIG. 3. Here, multiplexer 200 can sequentially multiplex the KF data frames₁ to KF_N. In this case, the multiplexed frame size is P = K₁ + K₂ + ... + K_N. Therefore, the multiplexer 200 first determines the number N of transport channels, receives radio frames in parallel from the radio frame adapters 101 to 10N, and sequentially multiplexes the data frames, to one data frame in Serie. That is, multiplexer 200 delivers a serial data frame, indicated 303 in FIG. 3.

A physical channel segmentation device 300, segments the multiplexed frame of size P, received from the multiplexer 200, into M physical channel frames, as indicated by 304 in Figure 3 (M is the number of physical channels available) , and feeds the physical channel frames to second interleaving devices 401 to 40N. Here, each physical channel frame is as long as P / M. Physical channels can use multiple codes. Thus, the physical channel segmentation device 300 sets the number M of available physical channels, segments the multiplexed serial data frame into M physical channel frames, and assigns the corresponding physical channels to these. The multiplexed serial data frame may be segmented into one or more physical channel radio frames of the same data rate. Alternatively, the multiplexed serial data frame can be segmented into one or more physical channel frames of different data rates.

An uplink channel receiving device, for receiving radio frames from the uplink channel transmitting device shown in Fig. 1, performs the operation of the uplink channel transmitting device, in reverse order. The uplink channel receiving device will be described below with reference to Fig. 4.

The operation of each component shown in figure 1 is illustrated in detail in figure 3.

With reference to Figure 3, the reference number 301 denotes the segmentation of the transport channel frames, received in parallel from the first interleaving devices 111a 11N, into radio frames that will be transmitted from the frame segmentation devices of radius 121 to 12N. If Lj / Tj is not an integer, a corresponding radio frame segmentation device inserts a stuffing bit to make L, a multiple of T,. As shown in Figure 3, padding bits are inserted sequentially, in radio frames, preferably starting with the last radio frame.

Reference numeral 301 in Figure 3 illustrates the procedure for adding padding bits in radio frames. The procedure is explained in detail in subsequent sections. The embodiment of the present invention is described in the context of the case where a 0 or 1 stuffing bit is inserted into a radio frame. Reference numeral 302 indicates the rate adaptation of radio frames, according to their data rates. Reference number 303 indicates the multiplexing of N radio frames of size K, (i = 1, 2, ..., N), after rate adaptation, to a multiplexed frame of size P, and the transmission of the multiplexed frame to the physical channel segmentation device 300. Reference number 304 indicates the segmentation of the multiplexed frame, into M physical channel frames, and the parallel assignment of the M physical channel frames, to the physical channels.

Figure 2 is a block diagram of a downlink channel transmission device, for downlink channel encoding and multiplexing, illustrating radio frame adapters 151 to 15N, up to second interleaving devices 800.

The downlink channel transmission device operates in the same way as the uplink channel transmission device shown in Figures 1 and 3, except that the outputs of the devices

ES 2 269 880 T3 of radio frame segmentation 171 to 17N, are applied to the input of the multiplexer 600. The speed adapters are not shown in the drawing, because they are arranged before the first interleaving devices, in the downlink channel transmission device of Figure 2.

A downlink channel receiver has the same operation as the uplink channel receiver, except that it does not perform rate adaptation reversal.

A description will be given, mainly of the radio frame segmentation devices, the multiplexers, and the physical channel segmentation devices, in the channel transmission devices constituted as shown in Figures 1 and 2. For the best In understanding the present invention, the description will be limited to the uplink channel transmission device. Therefore, the radio frame segmentation devices are labeled 121 to 12N, the multiplexer 200, and the physical channel segmentation device 300.

Radio Frame Segmentation Using Fill Bit

The uplink and downlink radio frame segmentation devices work in the same way. Radio frame segmentation devices 121 to 12N segment input transport channel frames into 10 ms radio frame blocks and deliver the radio frames sequentially. During this operation, padding bits may or may not be inserted into a transport channel frame, according to the bit number of the transport channel frame. In the embodiment of the present invention, insertion of filler bits is carried out in radio frame segmentation devices 121 to 12N, if filler bits are inserted. A stuffing bit is inserted into a radio frame, and the insertion of the stuffing bit begins with the last radio frame. A description of the insertion of a stuffing bit into a transport channel frame, and after segmentation of the transport channel frame into radio frames, in radio frame segmentation devices 121 to 12N, in reference with figure 5, it will precede that of the segmentation of a transport channel frame into radio frames, without the insertion of filler bits in the radio frame segmentation devices 121 to 12N, with reference to figure 6.

In the case that the ratio (L, / Tj), of the size of a transport channel frame applied to the input of a radio frame segmentation device, between the radio frame TTI, is not an integer, the number, r, of padding bits is calculated as follows, to make L, / T, an integer. Since T, varies from 0 to 8, r, varies from 0 to 7. (L, r,) / T ,, achieved with the use of padding bits, is defined as KD, and R, respectively for the downlink and for the uplink.

r, = T, - (L_t mod T¡), here r, = {0, 1, 2, 3, 4, 5, 6, 7} downlink: KD, = (LD, + rD_j) / TD_j; LD ,, rD, and TD, are L ,, r, and T, for the downlink, respectively uplink: R, = (L, + r,) / T,

If the number r, of stuffed bits is not 0, a stuffing bit is added to the position of the last bit of each of the corresponding radio frames, from a radio frame (T, - r, + 1) -th, to keep a constant frame length, that is, KD, or R ,. 0 or 1 is arbitrarily selected as the fill bit. The padding bit has little to do in terms of performance, and serves as a reserved bit, which can be selected by a system user. It can be contemplated that the stuffing bit is designated as a discontinuous transmission bit (DTX), such that a transmitter does not transmit the stuffing bit after channel coding and multiplexing. The radio frame blocks that are modified in the above manner, to have a constant radio frame length, are supplied to the multiplexer 200. The operation of the bit-based radio frame segmentation devices will then be described in detail. .

Regarding the bits prior to radio frame segmentation in an i-th 10i radio frame adapter, it is assumed that the number r, of padding bits has already been calculated, and 1 <t <T, (t indicates a radio frame index). t = 1 for the first radio frame, t = 2 for the second radio frame, and t = T, for the last radio frame. Each radio frame has the same size, (L, + r,) / T ,. Then, the output bits of a first interleaver device 111 of the ith radio frame adapter 10i are taken as b ,,₁, b ,,₂, b ,,₃, ..., b ,, _L,, and the output bits of the radio frame segmentation device 12i are taken as c ,,₁, c ,,₂, ... c ,,_[(L,+_I,_{) / T},_] in a 10 ms radio frame unit, for T, = TTI (msec) of the i-th transport channel / 10 (msec) e {1, 2, 4, 8}. Then radio frame segmentation device output bits, for the first 10 ms: t = 1 c, j = b, j, j = 1, 2, ..., (L, + i,) / T, radio frame segmentation device output bits, for seconds 10 ms: t = 2^C, j = ^b,, (j + (L, + Ii) / Ti))^{, j} = ^{1 2}> ...^{, (L}, + ^I,^{) / T},

ES 2 269 880 T3 radio frame segmentation device output bits, for the (T, - r,) -th 10 ms: t = (T, - r,) ^cij = ^bi, (j + (Ti-ri-1) (Li + ri) / Ti))> j = ^{1 2}»...» (L¡ + r¡) / T¡ output bits of the radio frame segmentation device, for the (T, - r_i + 1) -th 10 ms: t = (Ti-r, + 1) ^cij = ^bi, (j + (Ti-Ii) (Li + ri) / Ti))^{, j} = ¹» 2, ...» ^(Li + ^ri - ^{1) / T}ic_ij = filler _bit (0/1), j = (L, + r_i) / T_i output bits of the radio frame segmentation device, for the T, -th 10 ms: 1 = 1, ^cij = ^bi, (j + (Ti — ιί) ^,) ^,)) » ^j = ¹» ²» ...» ^(Li + ^ri ^{- 1) / T}ic_ij = filler _bit (0/1), j = (L, + r_i) / T_i

The radio frame segmentation device 12i is included in a transmitting device, and is the counterpart to a radio frame segmentation inversion device, in a receiving device. Radio frame segmentation inversion is equivalent to the inverse operation of radio frame segmentation, in that the 10 ms blocks received during a transmission period are arranged sequentially and assembled into a frame.

Figure 5 illustrates a radio frame generation process, using padding bits in the manner described above. The variables used below will be defined first.

t: radio frame index (1, 2, ..., T,);

RF_i,_t: a t-th radio frame of 10 ms, on an ith radio frame adapter; Y

Li: input frame size, from the ith radio frame adapter.

Referring to Figure 5, the radio frame segmentation device carries out an initialization process in step 511:

t: 1 / * radio frame index initialization * / ri: = Ti - Li mod Ti / * number of stuffing bits * /

Ri: = (Li + ri) / Ti for UL (uplink) / * radio frame size for uplink * /

KD ,: = (LD, + rD_i) / TD_i for DL ​​(downlink) / * radio frame size for downlink * /

In step 513, the radio frame segmentation device checks whether the number r, of padding bits is 0. If the number ri of padding bits is 0, the radio frame segmentation device reads data from one of radio frame, measured from an input frame, and stores them in step 517. On the other hand, if the number ri of padding bits is not 0; the radio frame segmentation device checks if a frame index t is (T, - r, + 1) in step 515, that is, a padding bit is to be added to a radio frame. In the case of a radio frame to which a padding bit has not been added, the data radio frame segmentation device reads a measured radio frame from an input frame, and stores it in step 519 , and go to step 525. In the case of a radio frame to which a padding bit is added, the radio frame segmentation device reads data, one bit smaller than a radio frame, measured from the input frame, and stores it in step 521. The radio frame segmentation device inserts the position of the last bit of the radio frame stored in step 523, increments the frame index t by 1, in step 525, and checks whether the updated frame index t is greater than the segment number T, corresponding to the radio frame TTI in step 527. If the frame index t is less than the segment number T, corresponding to the radio frame TTI, the radio frame segmentation device returns to step 513. If the frame index t is greater than the segment number Ti corresponding to the radio frame TTI, the radio frame generation procedure ends. The radio frames thus generated are supplied sequentially to the second multiplexer 200.

ES 2 269 880 T3

Radius Frame Segmentation Without Fill Bit Insertion

A radio frame segmentation device that did not use padding bits can be used instead of the radio frame segmentation device described above. Since T, varies from 0 to 8, r, varies from 0 to 7. (L, + r ^ / T, for downlink and uplink, are defined as KD, and R ,, respectively.

r, = T, - (L, mod T,), here r, = {0, 1, 2, 3, 4, 5, 6, 7} downlink: KDi = (LDi + rDi) / TDi uplink: R, = (L, + r,) / T,

The bit-based operation of the radio frame segmentation device using no filler bits will be described in detail.

Regarding the bits prior to radio frame segmentation, in the i-th radio frame adapter 10i, it is assumed that the number r, of padding bits has already been calculated, and 1 <t <T, ( t indicates a radio frame index). t = 1 for the first radio frame, t = 2 for the second radio frame, and t = Ti for the last radio frame.

Then let be the output bits of the first interleaver 11 at the ith radio frame adapter 10i, b¡, i, b ,,₂, b ,,₃, ..., b ,, _L,, and let be the output bits of the radio frame segmentation device 12i, c,₄, c ,,₂, ... ci, (li + ii) / ti, in a 10 ms radio frame unit for T, = TTI (msec) of the i-th transport channel / 10 (msec) e {1, 2, 4, 8}. Then radio frame segmentation device output bits, for the first 10 ms: t = 1 c, j = b, j, j = 1, 2, ..., (L, + i,) / T, radio frame segmentation device output bits, for seconds 10 ms: t = 2^C, j = ^b¡, (J + (L¡ + r¡) / T¡))^{, j} = ^{1 2} ...^{, (L}, + ^Ií^{) / T}í radio frame segmentation device output bits, for the (T, - r,) - th 10 ms: t = (T, - r,) ^C, j = ^b,, (j + (T, -I, -1) (L, + I,) / (T,))^{, j} = ^{1 2} ...^{, (L}, + ^Ií^{) / T}í radio frame segmentation device output bits, for the (T, - r, + 1) -th 10 ms: t = (T, - r, + 1) ^c, j = ^b,, (j + (T, -i,) / L, + i,) / T,))^{, j} = ^{1 2}, ...^{, (L}, + ⁱí^{) / T}í output bits of the radio frame segmentation device, for the T, -th 10 ms: t = T, ^c, j = ^b,, (J + (T, -i,) (L, + i,) / T,))^{, j} = ^{1 2}, ...^{, (L}, + I¡^{) / T}¡

If r is not 0, the size of the first radio frames to (T, - r,) - th is R ,, and the size of the radio frames (T, - r, + 1) -th to last is (R, - 1). For the downlink, if rD, is not 0, the size of the first radio frames to (TD, - rD,) - th is KD ,, and the size of the radio frames (TD, - rD, + 1 ) -th to last is (KD, - 1). Radio frame blocks of time varying sizes are supplied to the multiplexer. Due to the variable size of the radio frame, a frame size in the multiplexer may vary in each 10 ms interval, and the physical channel segmentation device may further operate differently in each 10 ms interval, making it difficult to operate. frame size control. Therefore, it is preferable to use a radio frame segmentation device, which inserts padding bits.

The radio frame segmentation device 12i is included in a transmitting device, and is the counterpart to a radio frame segmentation inversion device, in a receiving device. Radio frame segmentation inversion is equivalent to the inverse operation of radio frame segmentation, in that the 10 ms blocks received during a transmission period are arranged sequentially and assembled into a frame.

Figure 6 illustrates a radio frame generation process, without inserting filler bits, in the manner described above. The variables used here are defined first.

ES 2 269 880 T3 t: radio frame index (1, 2, T_i);

RF_i,_t: a t-th radio frame of 10 ms, in an-th encoding and multiplexing chain; Y

L: input frame size, from the ith radio frame adapter.

Referring to Figure 6, the radio frame segmentation device performs an initialization process in step 611:

t: 1 / * radio frame index initialization * / r_i: = T_i - L mod T_i / * number of padding bits * /

R_i: = (L_i + r_i) / T_i for UL (uplink) / * radio frame size for uplink * /

KD_i: = (LD_i + rD_i) / TD_i for DL ​​(downlink) / * radio frame size for downlink * /

In step 613, the radio frame segmentation device checks if the number ri of stuffing bits is 0. If the number ri of stuffing bits is 0, the radio frame segmentation device reads data of a size radio frame, from an input frame, and stores them in step 617. On the other hand, if the number r_i number of padding bits is not 0, the radio frame segmentation device checks whether a frame index t is (T_i - r_i + 1), in step 615. If the frame index t is less than (Ti - ri + 1), the radio frame segmentation device reads data from a measured radio frame from an input frame, and memorizes them in step 619 and goes to step 623. If the frame index t is equal to or greater than (Ti-ri + 1), the radio frame segmentation device reads data, one bit smaller than a frame radio, measured from the input frame, and stores them in step 621. The radio frame segmentation device increments the frame index t by 1 in step 623, and checks if the updated frame index t is greater than the segment number Ti corresponding to the radio frame TTI, in step 625. If the frame index t is less than the segment number Ti corresponding to the radio frame TTI, the radio frame segmentation device returns to step 613. If the frame index t is greater than the segment number T_icorresponding to the radio frame TTI, the radio frame generation procedure ends. The radio frames thus generated are supplied sequentially to the second multiplexer 200.

Multiplexed

The multiplexer 200 for the uplink will be described. The bits described below are applied to the input of multiplexer 200:

speed adapter output bits # 1: c_or, c_i2..., c_i,_Kispeed adapter # 2 output bits: c₂,_i, c₂,₂, ..., c₂,_K2speed adapter output bits # 3: c₃, i, c₃,₂, ..., c₃,_K3 speed adapter output bits #N: c_Neither c_N,₂, ..., c_N,_KN

The output bits di, d₂, ... d_p of multiplexer 200 are: when j = 1, 2, 3, ..., P (P = Ki + K2 + ... + Kn), toCij j = l, 2, dj⁼ ^ Xr-K ') j = K, + l, K | + 2, K | + K₂ DJ^ec3Xj- (Ki * K2)) j ⁼ (K | + Kj) +1, (K, + K₂) +2, (Ki + ICjI + Kj dj “ ^CNXj- <Kl⁺Ki + .- + KM-l)) j = (K, + K2 + ... + Kn _,) + 1, (K, + K2 + ... ⁺Kn_i) +2, (K, + K2 + ...

Then, the operation of the multiplexer 200 for the downlink is described below.

ES 2 269 880 T3

The bits described below are applied to the input of the multiplexer 200: output bits of the speed adapter # 1: c₁,₁, c₁₂, ..., c₁,_K1speed adapter # 2 output bits: c₂,₁, c₂,₂, ..., c₂,_K2speed adapter output bits # 3: c₃,₁, c₃,₂, ..., c₃,_K3 speed adapter output bits #N: c_N,₁, c_N,₂, ..., c_N,_KN

The output bits d₁, d₂, ..., of multiplexer 200 are: when j = 1, 2, 3, ..., P (P = K1 + K2 + ... + KN), dj⁼ ° 2Λ-κΐ) dj = ^C3XHK '+ K2)) j ⁼ 1 »2 K, j = K, + l, K, + 2 ..... K, + K₂ j = (K. + K ^ l, (K. + KJ + 2, (K, + Kj) + K₃ DJ^{- C}N4H^{K1 + KJ +} -*^KN-D) j ~ (Kt + K2 + · · · ⁺Kh_i) +1, (K | + K2 + .. + Kn _,) + 2 ..... (K, + K₂+ ...

The multiplexer 200 is included in a transmitting device, and its counterpart is a demultiplexer in a receiving device. The demultiplexer carries out the inverse of the operation of multiplexer 200, that is, it segments an input frame into N blocks, and supplies the N blocks, to corresponding radio frame adaptation inversion devices.

FIG. 7 is a flow chart illustrating a radio frame multiplexing procedure in multiplexer 200. Prior to the description of the procedure shown in FIG. 7, the terms used below are defined.

N: total number of radio frame adapters;

i: radio frame adapter index (1, 2, ..., N); Y

RF ,: a 10 ms radio frame, on an i-th radio frame adapter.

The multiplexer 200 sets the radio frame adapter index i to an initial value of 1, in step 711, and stores a radio frame received from the ith radio frame adapter, in a multiplexing buffer, in step 713. In step 715, multiplexer 200 increments radio frame adapter index i by 1. Next, the multiplexer 200 checks if the increased index i is greater than the total number N of radio frame adapters in step 717. If i is equal to or less than N, multiplexer 200 goes to step 713. If i is greater than N, multiplexer 200 terminates the multiplexing process. As described above, the multiplexer 200 sequentially stores radio frames received from the radio frame adapters, in the multiplexing buffer, and generates a multiplexed frame of size P, which is a serial data frame.

Physical Channel Segmentation

The physical channel segmentation device 300 works the same way for the uplink and for the downlink.

Let d₁, d₂, ... d_p the bits of a serial data frame output from the multiplexer, and let M be the number of physical channels. So, physical channel frame segmentation device output bits, for physical channel # 1: e1, j = dj j = 1, 2, ..., P / M frame segmentation device output bits of physical channel, for physical channel # 2:^and2, j = d (j + p / M) ^j = 1» 2,...^{, P /}M

ES 2 269 880 T3 physical channel frame segmentation device output bits, for physical channel #M:

^andM, j = ^d(j + (M-1) P / M) ^j = 1, 2, ...^{, P /}M

The above physical channel segmentation scheme, in the physical channel segmentation device, is advantageous in that the best use is made of the achievements of the second interleaving devices. Therefore, the probability of bit errors after decoding in a receiver, caused by burst errors in an attenuated channel, can be minimized. For a 1/3 data rate for a general channel encoder, three symbols represent one bit of information. As shown below, another physical channel segmentation scheme with M = 3 and P = 30 can also be considered:

Bits before physical channel segmentation:

0123456789 10...29

Bits after physical channel segmentation: physical channel # 1: 0 3 6 9 12 ... 27 physical channel # 2: 1 4 7 10 13 ... 28 physical channel # 3: 2 5 8 11 14 ... 29

Since the second interleaving device is used in this segmentation of three physical channels, three input symbols are always consecutive after the second interleaving. Consequently, the three consecutive symbols are extremely likely to experience errors, fading at a specific time point.

Meanwhile, a segment that has consecutive bits of the same number is assigned to a physical channel in the present invention, and thus:

bits before physical channel segmentation: physical channel # 1: 0123 ... 9 physical channel # 2: 10 11 12 13 ... 29 physical channel # 3: 20 21 22 23 ... 29 bits after segmentation physical channel:

physical channel # 1: 0123 ... 9 physical channel # 2: 10 11 12 13 ... 29 physical channel # 3: 20 21 22 23 ... 29

After the second interleaving, three physical channels have different times in the same bit position, thereby decreasing the probability of concurrent errors in three representative symbols of an information bit, due to fading. Thus a receiver may have a lower bit error rate (BER) in the present invention, relative to the physical channel segmentation described above.

The physical channel frame segmentation device is included in a transmitting device, and its counterpart is a physical channel segmentation inversion device in a receiving device. The physical channel segmentation reversal device performs the reverse operation of the physical channel segmentation device, that is, sequentially arranges M physical channel frames, and assembles them into one frame.

Fig. 8 is a flow chart, illustrating a physical channel frame generation procedure, in the physical channel segmentation device. The terms used below will be defined first:

m: physical channel index (1, 2, ..., M)

M: total number of physical channels; and P: size in bits of the index data block.

Referring now to FIG. 8, the physical channel segmentation device 300 sets the physical channel index m to an initial value of 1, in step 811, and reads a P / M size data block from the input data. , of size

ES 2 269 880 T3

P, and stores it in an mth physical channel buffer, in step 813. Then, the physical channel segmentation device 300 increments the physical channel index m by 1, in step 815, and checks whether the Increased physical channel index m is greater than the total number M of physical channels, in step 817. If m is equal to or less than M, the physical channel segmentation device 300 returns to step 813. Conversely, if m is greater than M, physical channel segmentation ends.

Implementation of the Receiving Device

Figure 4 is a block diagram of a channel receiving device having the counterparts of the radio frame segmentation device, the multiplexer, and the physical channel segmentation device, as described above.

Referring to FIG. 4, a physical channel memory 411 stores the second interleaved symbols. A first address generator 412 generates a write address for each M bits of the second interleaved symbols, in which the M bits will be stored in the physical channel memory 411. A second address generator 413 generates a read address, to sequentially read symbols from physical channel memory 411, when the symbols are fully stored in physical channel memory 411. A demultiplexer 414 distributes symbols received from the physical channel memory 411, to N buffers 415 to 4N5. The buffers 415 to 4N5, supply the memorized symbols to corresponding radio segmentation inversion devices, 417 to 4N7, without rate adaptation inversion if the symbols are for downlink, and to the rate adaptation inversion devices 416 to 4N6, if the symbols are for uplink. Rate adaptation reversal devices 416 to 4N6 perform zero symbol insertion and symbol combining, in reverse order of rate adaptation. The radio frame segmentation inversion devices 417 to 4N7, assemble the symbols received from the rate adaptation inversion devices 416 to 4N6, to data from the corresponding transport channel TTIs, and transmit the data subjected to inversion of segmentation, to a channel decoder, for channel decoding.

For a write operation, the first address generator 412 operates to write every M bits to the physical channel memory 411, ie a buffer to store symbols received after the second interleaving reversion process. Therefore, the physical channel memory 411 receives a total of P symbols, from the second interleaver, running P / M times. When there is no data in each channel coding and multiplexing channel, the total number of received symbols is less than P. Thus, a maximum size of the buffer is P. After the write operation is completed, the second address generator 413 generates read addresses, and symbols are read from physical channel memory 411, in the order of address generation. The reading operation is carried out in (L¡ + r¡) / T¡ (= R¡) units. By reading N frames of size R, a total of P symbols is transmitted to the N buffers 415 to 4N5, through the demultiplexer 414. Each buffer has a size of T, x R, (i = 1, 2, 3, ... N). In this case, demultiplexer 414 serves to distinguish N symbols. The classified symbols are transmitted directly to the radio frame segmentation inversion devices 417 to 4N7, without undergoing speed adaptation inversion, if they are downlink, while the symbols are subjected to speed adaptation inversion. , if they are uplink. That is, the rate adaptation reversal devices 416 to 4N6 implement zero symbol insertion and symbol combining, which is the reverse operation of rate adaptation. The radio frame inversion devices 417 to 4N7 then transmit the inverted symbols to the corresponding channel decoders for channel decoding. As has been highlighted from the above description, the operation of the receiving device is basically the reverse of the operation of the transmitting device.

According to the present invention, as described above, the radio frame segmentation, multiplexing, and physical channel segmentation, for channel multiplexing and coding, is defined in detail. Frames of various types, generated from channel encoders, are converted into radio frames, multiplexed, and converted into physical frames. The physical frames are then assigned to physical channels. Therefore, the uplink and downlink transmission devices in a CDMA communication system can implement various communication services such as voice, data, and image transmission.