JP3181495B2 - Data rate determining device and data receiving device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION The present invention relates to, for example, a mobile station of a digital cellular type mobile telephone system.
The present invention relates to a data receiving apparatus that receives voice data encoded at a variable rate.

[0002] The present invention also relates to, for example, a data rate judging device for judging the data rate of received data in the data receiving apparatus.

[0003]

2. Description of the Related Art Generally, in a digital cellular mobile telephone system, a code division multiple access system (hereinafter referred to as "CDMA system") is employed as a multiple access system. As a mobile phone system adopting the CDMA system, there is a system described in the following document.

Document: TIA / EIA / IS-95 In the portable telephone system described in this document, when audio data is transmitted from a CDMA transmitter of a base station to a CDMA receiver of a mobile station, the audio data is transmitted at a variable rate. After encoding, the data rate is converted to a predetermined data rate and transmitted.

In such a configuration, the CD of the mobile station is
When reproducing the original audio data from the received data in the MA receiver, it is necessary to determine the data speed before the speed conversion of the received data.

Conventionally, when determining the data speed of the received data before the speed conversion, the data speed before the speed conversion of the received data is assumed to be a certain speed, and the original voice data is reproduced from the received data according to the assumed speed. Until the original audio data can be accurately reproduced, the data reproduction process is performed while changing the assumed speed, thereby making the determination.

[0007]

However, in such a configuration, in the worst case, the data reproduction process must be performed by the number of data speeds, so that there is a problem that the data speed determination time becomes long.

[0008]

In order to solve the above-mentioned problems, the invention according to claim 1 divides one or a plurality of frames of received data equally for each frame by a number corresponding to a speed conversion ratio. Then, of the plurality of divided portions obtained by this division, it is determined whether or not the same divided portion of the data pattern exists by a predetermined ratio, and based on the determination result, the speed of the received data before the speed conversion is determined. The data rate is determined.

The invention according to claim 8 provides a data receiving apparatus having the data rate determining function according to claim 1.

[0010]

Embodiments of the present invention will be described below in detail with reference to the drawings.

In the following description, the present invention will be described by referring to the CD of the mobile station of the portable telephone system described in the above-mentioned document.
A case where the present invention is applied to an MA receiver will be described as a representative. Therefore, in the following description, for simplicity of explanation, in addition to the CDMA receiver of the mobile station, the CDM of the base station will be described.
The A transmitter will also be described.

[CDMA Transmitter] First, a CDMA transmitter of a base station will be described.

[Configuration] FIG. 2 is a block diagram showing an example of a configuration of a CDMA transmitter for a traffic channel of a base station.

The CDMA transmitter shown in FIG.
01, a tail bit adding unit 102, a convolutional coding unit 103, a data repetition unit 104, and a block interleave unit 105.

Here, the CRC adding section 101 has a function of adding a CRC bit to audio data encoded at a variable rate.

The tail bit adding unit 102 has a function of adding tail bits to audio data to which CRC bits have been added.

The convolution unit 103 has a function of performing convolutional encoding on audio data to which tail bits have been added.

The data repetition section 104 has a function of repeatedly outputting convolutionally encoded audio data in a bit unit, one number smaller than the number corresponding to the speed conversion ratio.

The block interleave section 105 has a function of performing block interleave processing on audio data that has undergone data repetition processing.

[Operation] The operation of the above configuration will be described.

The audio data to be transmitted is encoded by an encoding unit (not shown). In this case, the audio data is
Encoding is performed at a rate corresponding to the amount of speech of the sender. this is,
This is for improving the transmission efficiency of audio data.

In the portable telephone system described in the above document, a coding rate of 16 bits (0.8 kbps) per frame, a coding rate of 40 bits (2.0 kbps), and a coding rate of 80 bits (2.0 kbps). Four types of speed are used: a speed that allocates 4.0 kbps) and a speed that allocates 172 bits (8.6 kbps).

The audio data encoded at the variable rate is
The data is supplied to the CRC adding unit 101, where the CRC bit is added. This is to improve the quality of the frame.

However, this CRC bit addition process is performed only on the audio data having the encoding speed of 9.6 kbps and 19.2 kbps, and the encoding speed is 4.0 kbps.
And 8.6 kbps audio data.

Note that the coding speed is 9.6 kbps, 1
The number of CRC bits added to the 9.2 kbps audio data is 8 and 12, respectively.

The audio data output from the CRC adding unit 101 is supplied to a tail bit adding unit 102, and eight tail bits are added to each frame. Thereby, the coding speed is 0.8 kbps, 2.0 kbps.
s, 4.0 kbps, 8.6 kbps audio data,
The data rates are 1.2kbps and 2.4kbp, respectively.
s, 4.8 kbps, 9.6 kbps.

The audio data to which the tail bit has been added is
The signal is supplied to the convolutional coding unit 103 and is subjected to convolutional coding at a coding rate of 1/2. As a result, the data rate of the audio data is doubled (2.4 kbps, 4.8 kbps, 9.6 kps).
bps, 19.2 kbps). Hereinafter, these four types of data rates are referred to as baseband data rates.

The convolutionally encoded audio data is supplied to a data repetition unit 104, and is repeatedly output in units of bits by subtracting one from the number corresponding to the speed conversion ratio. Thus, the data speed of the audio data is converted to a predetermined speed.

In this case, the predetermined data rate may be, for example, the largest baseband data rate 1
9.2 kbps is used. Thereby, the data rate of the baseband is 19.2 kbps, 9.6 kbps,
The 4.8 kbps and 2.4 kbps audio data undergo data repetition processing 0 times, 1 time, 3 times, and 7 times, respectively. It should be noted that receiving the data repetition process 0 times actually means not receiving the data repetition process.

The audio data subjected to the data repetition processing is
It is supplied to the block interleaving section 105 and undergoes block interleaving processing in the same frame. As a result, audio data in which predetermined blocks are repeatedly inserted into the frame after the speed conversion by the number corresponding to the speed conversion ratio is obtained.

The above-mentioned block converts data included in the frame before the speed conversion into data, for example, according to a predetermined rule.
It is composed of data obtained by rearranging in bit units.

The audio data that has been subjected to the block interleave processing has a power control bit added thereto,
Spread modulation is performed using a Walsh code. This results in a data rate of 1.2288 Mcps (chips per second)
Is obtained.

The spread-modulated voice data is transmitted through an antenna after undergoing digital modulation processing such as PSK modulation.

The above is the configuration and operation of the CDMA transmitter on the traffic channel of the base station.

Here, the above-described data repetition processing and block interleaving processing will be described using specific examples. In the following description, the data rate of the baseband is 9.
6 kbps audio data will be described as a representative.

For the sake of simplicity, assume that the number of bits for one frame of the audio data is four. Also, the bit string for one frame of the audio data is represented by “1, 2,
3, 4 ".

The voice data is transmitted to a data repetition unit 104
And subjected to data repetition processing. In this case, since the voice data has a speed conversion ratio represented by (1: 2),
One data repetition process is performed. As a result, the audio data is changed from “1, 2, 3, 4” to “1, 1, 2, 2, 3,
3, 4, 4 ".

The voice data subjected to the data repetition processing is
It is supplied to the block interleave section 105 and undergoes block interleave processing. Thereby, the audio data is converted from, for example, “1, 1, 2, 2, 3, 3, 4, 4” to “1, 4, 2, 3, 1, 4, 2, 3”.

That is, the audio data is obtained by rearranging the data “1, 2, 3, 4” included in the frame before the speed conversion according to a predetermined rule, and obtaining the data “1,
The block composed of "3, 2, 4" is converted into data in which the frame after the speed conversion is repeatedly arranged by the number 2 according to the speed conversion ratio.

The above is a specific example of the data repetition processing and the block interleaving processing.

[Embodiment] Next, an embodiment of the present invention will be described. That is, the CDMA receiver of the mobile station will be described.

[Configuration] FIG. 1 is a diagram showing CDMA in a traffic channel of a mobile station.
FIG. 3 is a circuit diagram illustrating a configuration of a receiver.

The illustrated CDMA receiver includes a de-interleave section 201, a data buffer section 202, a data accumulation section 203, a Viterbi decoding section 204, and a binary decision section 205.
A determination result storage unit 206, a majority determination unit 207,
It has a speed determination unit 208.

Here, the de-interleave unit 201, the data buffer unit 202, the data accumulation unit 203, and the Viterbi decoding unit 204 operate according to the baseband data rate of the received data determined by the data rate determination unit described later. And an audio data reproducing unit for reproducing the original audio data from the received data.

Also, a binary determination section 205, a determination result storage section 206, a majority determination section 207, and a speed determination section 208
Constitutes a data rate determination unit that determines the baseband data rate of the received data.

This data speed judging unit has two speed judging functions, a speed judging function based on a ratio and a speed judging function based on a reproduction result.

Here, the speed determination function based on the ratio is based on the assumption that the baseband data speed of the received data is a certain speed, and that the number of received data is equal to the ratio between the assumed speed and the converted data speed. This is a function of equally dividing data for one frame and determining the baseband data rate of the received data based on the ratio of the number of the same divisions in the data pattern to the number of all divisions.

The speed judgment function based on the reproduction result is as follows.
Suppose a certain speed velocity unconverted data rate of the received data, based on the reproduction result of the received data in accordance with this assumption the speed, in determining <br/> function data rate before rate conversion of the received data is there.

In the speed judgment based on the ratio, 4
Baseband data rates of 2.4 kbps, 4.8
kbps, 9.6 kbps, 19.2 kbps
For example, the lower two data rates are 2.4 kbps,
4.8 kbps is determined. On the other hand, in the speed determination based on the reproduction result, the faster two data speeds of 9.6 kbps and 19.2 kbps are determined.

In the audio data reproducing section, the de-interleave section 201 has a function of performing de-interleave processing on the received data.

The data buffer unit 202 has a function of temporarily holding the received data that has been subjected to the de-interleaving process. The data buffer unit 202 has a capacity capable of storing two frames of received data. When one frame of received data is stored, the data buffer unit 202 immediately supplies the received data to the data accumulating unit 203.

The data accumulating section 203 has a function of repeatedly accumulating the received data supplied from the data buffer section 202 in units of bits by subtracting 1 from the number corresponding to the speed conversion ratio.

The Viterbi decoding unit 204 has a function of Viterbi decoding received data that has been subjected to data accumulation processing.

In the data rate determining section, the binary determining section 2
05 is 0 or 1 for each bit of the received data.
It has a binary decision function to decide whether or not. This determination is made for one frame.

The determination result storage unit 206 stores the binary determination unit 20
5 has a function of storing the determination result.

The majority decision unit 207 sets the baseband data rate of the received data to 2.4 kbps or 4.8 kps.
bps, the determination result for one frame of the received data is evenly divided by 8 or 4 according to the ratio between the assumed speed and the data speed after the conversion of 19.2 kbps. Of the eight or four divisions,
It has a function of determining whether or not the number of the same divisions of the data pattern occupies a majority of the whole.

The speed judging unit 208 includes a majority judging unit 207
Has a function of determining whether the baseband data rate of the received data is 2.4 kbps or 4.8 kbps based on the determination result.

Further, this speed determining section 208 assumes that the baseband data rate of the received data is 9.6 kbps or 19.2 kbps, and based on the reproduction result of the received data according to this assumed speed, Baseband data rate of 9.6 kbps or 19.2 kbps
Has the function of determining whether

[Operation] The operation of the above configuration will be described.

First, the operation of the audio data reproducing section will be described.

The modulated signal of the traffic channel transmitted from the base station is digitally demodulated after being received by the antenna of the CDMA receiver. As a result, audio data having a data transmission rate of 1.2288 Mcps can be obtained.

This voice data is despread using the same Walsh code as the Walsh code for spreading used in the CDMA transmitter of the base station. As a result, audio data having a data rate of 19.2 kbps is obtained.

The audio data is supplied to the deinterleave unit 2
01, and undergoes a de-interleaving process for each frame. As a result, the audio data is changed from “1, 4, 2, 3, 1, 4, 2, 3” to “1,
1, 2, 2, 3, 3, 4, 4 ".

The audio data subjected to the de-interleave processing is temporarily stored in the data buffer unit 202,
The data is supplied to the data accumulating unit 203.

The audio data supplied to the data accumulating section 203 is repeatedly accumulated for each bit by a number smaller than the number corresponding to the speed conversion ratio by one.

As a result, the data rate of the baseband of the audio data is 2.4 kbps, 4.8 kbps, 9.6.
kbps and 19.2 kbps, 7 times each,
The data is accumulated three times, once, and zero times. here,
Receiving zero data accumulation processing means that data accumulation processing is not substantially performed.

The speed conversion ratio is a unified speed of 1
It is determined in accordance with the data rate of 9.2 kbps and the baseband data rate of the reception data determined by the rate determination unit 208.

By the above-described data accumulation processing, the data rate of the audio data is returned to the data rate of the base band. Further, the frame structure is returned to the frame structure before the speed conversion. In the previous example, the audio data is "1,
1,2,2,3,3,4,4 "to" 1,2,3,4 "
Is returned to.

The audio data subjected to the data accumulation processing is supplied to the Viterbi decoding unit 204. This Viterbi decoding unit 20
No. 4 performs Viterbi decoding from the data of one frame by the number corresponding to the data rate according to the data rate determined by the rate determination unit 208. This allows the data rate to be 1.
2 kbps, 2.4 kbps, 4.8 kbps, 9.6
kbps audio data is obtained.

The Viterbi-decoded audio data has an 8-bit tail bit deleted by a tail bit deletion unit (not shown). As a result, the data rate is 0.8 kbp
s, 2.0 kbps, 4.4 kbps, 9.2 kbps
Is obtained.

Of the audio data from which the tail bits have been deleted, data having a data rate of 0.8 kbps and 2.0 kbps are decoded into analog audio data. On the other hand, data having a data rate of 4.4 kbps and 9.2 kbps are subjected to error detection processing using CRC bits and then decoded into analog audio data.

The operation of the audio data reproducing section has been described above.

Next, the operation of the data rate determining section will be described.

The audio data demodulated by the despreading is further supplied to a binary decision unit 205. Binary judgment section 20
5 is 0 or 1 for each bit.
Is determined. This binary determination is performed for one frame.

The judgment result is stored in the judgment result storage unit 206. When the determination result for one frame is stored, the determination result storage unit 206 supplies the result to the majority determination unit 207.

Upon receiving the determination result for one frame, majority decision determiner 207 assumes that the baseband data rate of the received data is 2.4 kbps, and divides the determination result for one frame into eight equal parts. It is determined whether or not the same division of the data pattern occupies the majority 5 of the total number of divisions 8 among the obtained eight divisions.

Upon receiving the determination result for one frame, the majority determination unit 207 assumes that the baseband data rate of the received data is 4.8 kbps, and divides the determination result for one frame into four equal parts. It is determined whether or not the same division of the data pattern occupies the majority 3 of the total number of divisions 4 among the four divisions obtained by this division.

These determinations may be made in order,
It may be performed simultaneously. When the determination is performed sequentially, the amount of hardware for the determination is small, but the determination time is long.
Conversely, if they are performed simultaneously, the amount of hardware increases, but the determination time becomes short.

In the case where the operations are performed in order, in the first judgment,
If it is determined that they occupy the majority, the second determination may be omitted. In this way, the determination time can be reduced when it is determined in the first determination that it occupies the majority.

The result of the decision by the majority decision unit 207 is supplied to the speed decision unit 208. The speed determination unit 208, in parallel with the determination operation of the majority judgment unit 207, first, the data rate of the baseband of the received data assuming 9.6 k b ps, this assumption speed and data accumulation unit 203, Viterbi Notify the decoding unit 204.

[0081] Thus, the data rate of the baseband reception data as 9.6 k b ps, the data accumulation process and the Viterbi decoding process is performed. The decoding result of this Viterbi decoding process is supplied to the speed determination unit 208.

[0082] speed determining unit 208, the decoding result of this assumption rate can be obtained, in turn, the data rate of the baseband of the received data assuming 19.2k b ps, this assumption speed and data accumulation section 203 , To the Viterbi decoding unit 204.

[0083] Thus, the data rate of the baseband reception data as 19.2k b ps, the data accumulation process and the Viterbi decoding process is performed. The decoding result of this Viterbi decoding process is supplied to the speed determination unit 208.

The speed judging section 208 includes a majority judging section 207
And the decoding result of the Viterbi decoding unit 204 according to the assumed speed, the baseband data speed of the received data is determined.

In this case, assuming that the baseband data rate of the received data is 2.4 kbps, if the majority decision result is “occupies a majority”, the data rate is determined to be 2.4 kbps. Also, if the majority decision result assuming that the baseband data rate of the received data is 4.8 kbps is "occupies the majority", the data rate is determined to be 4.8 kbps.

Furthermore, if the reproduction result (Viterbi decoding result) when the baseband data rate of the received data is assumed to be 9.6 kbps is normal, the data rate is 9.6 kps.
bps. If the reproduction result (Viterbi decoding result) when the baseband data rate is assumed to be 19.2 kbps is normal, the data rate is 19.2 kb.
ps is determined.

When the determination of the data rate is completed, the speed determining section 208 stores the determined data rate in the data accumulating section 203.
Is notified to the Viterbi decoding unit 204. Thereby, as described above, the data accumulation processing and the Viterbi decoding processing are executed according to the determined data rate.

The above is the operation of the embodiment.

The data rate is 2.4 kbps or 4.
When judging whether the data pattern is 8 kbps, instead of judging whether or not the number of the same divisions of the data pattern is the same as the total number of divisions, it is judged whether or not the number occupies the majority of the total number of divisions. For the following reasons:

That is, when the data rate is 2.4 kbps or 4.8 kbps, the frame after the rate conversion includes eight or four blocks. Therefore,
Baseband data rate of received data is 2.4 kbp
When determining whether the number is s or 4.8 kbps, it is conceivable to determine whether or not the same division part of the data pattern exists by the number of divisions 8 or 4.

However, when voice data is transmitted from a base station to a mobile station, noise is usually added to the voice data. As a result, the data in the frame is inverted, and a data error occurs in the received data.

When a data error occurs in the received data, the number of divisions having the same data pattern becomes less than eight or four. Therefore, in a configuration in which it is determined whether or not the number of divisions having the same data pattern is the same as the number of divisions, when a data error occurs, the data speed cannot be accurately determined.

In order to solve this problem, it is only necessary to lower the threshold value for determination. However, when the number of divisions having the same data pattern is smaller than the number of divisions of 8 or 4, the baseband data rate of the received data is 9.6.
kbps or 19.2 kbps. Therefore, if the threshold for determination is too low, in such a case, the data rate becomes 2.4 kbps or 4.8 kps.
bps may be erroneously determined.

Therefore, in this embodiment, when the number of the same divisions in the data pattern reaches a majority, the baseband data rate of the received data is determined to be 2.4 kbps or 4.8 kbps.

According to such a configuration, even if a data error occurs, it is possible to accurately determine whether the baseband data rate of the received data is 2.4 kbps or 4.8 kbps. When the baseband data rate of the received data is 9.6 kbps or 19.2 kbps, the data rate is 2.4 kbps or 4.8.
kbps can be prevented from being erroneously determined.

This is because if the number of divisions having the same data pattern does not reach the number of divisions 8 or 4 due to the occurrence of a data error, the probability that the number of divisions reaches a majority is high, and the base of the received data is high. Band data rate is 9.6
If the number of the same divisions of the data pattern does not reach the number of divisions 8 or 4 due to kbps or 19.2 kbps, there is a high probability that the number of divisions does not reach the majority.

FIG. 3 shows a frame structure of audio data after speed conversion. Here, (a) shows the frame structure of audio data when the baseband data rate is 2.4 kbps, and (b) shows the frame structure of audio data when the data rate is 4.8 kbps. .

In FIG. 3, in order to simplify the drawing,
The bit number of one frame after the speed conversion is set to 32 instead of the original 384. Even in this case, the characteristics of the frame are not different from the case of 384 bits.
No problem.

In FIG. 3A, the data pattern of one block of the 2.4 kbps audio data is represented by “0, 1,
In FIG. 3B, the data pattern of one block of the 4.8 kbps audio data is set to “0, 0, 1, 1”.
0, 1, 1, 0, 1 ".

As shown in FIG. 3A, when the baseband data rate is 2.4 kbps, the frame after the rate conversion includes eight blocks having the same data pattern. This is shown as B1 to B8. Similarly, when the baseband data rate is 4.8 kbps, the frame after the rate conversion includes four blocks having the same data pattern. This is shown as B1 to B4.

Therefore, when no data error occurs, the data rate of the received data is determined to be 2.4 kbps or 4.8 kbps by determining whether there are eight or four identical divisions of the data pattern. be able to.

However, when a data error occurs,
As shown in FIGS. 4A and 4B, the number of blocks having the same data pattern is less than eight or four. Therefore, in this case, in a configuration in which it is determined whether there are eight or four divisions having the same data pattern, it is not possible to determine the data rates of the received data as 2.4 kbps and 4.8 kbps.

FIG. 4 (a) shows a case where a data error has occurred in 2.4 kbps audio data, and FIG.
This shows a case where a data error has occurred in the 4.8 kbps audio data. The data error includes a burst error e1 in which data is erroneous over several bits and a bit error e2 in which only one bit is erroneous.

In the case of FIG. 4A, since the number of the same divisions in the data pattern occupies the majority 5 of the total number of divisions 8, the data rate is 2.4 kbps despite the occurrence of data error. Is determined. In contrast, FIG.
In the case of (b), the data rate is 4.8 because the number of the same divisions of the data pattern does not occupy the majority 3 of the total number of divisions 4.
If it is not kbps, it is erroneously determined.

[Effects] According to this embodiment described in detail above, the following effects can be obtained.

(1) First, according to this embodiment, 4
8. data rates 2.4 kbps, 4.8 kbps, 9.
2.4 kbps out of 6 kbps and 19.2 kbps
For s, 4.8 kbps, the data rate is determined by the rate determination based on the ratio, so that the data rate determination time can be reduced.

That is, conventionally, all four data speeds are determined by speed determination based on the reproduction result.

However, in such a configuration, it is necessary to perform the reproduction process four times in the worst case until the data speed is determined. Specifically, it is necessary to perform three data repetition processes and four Viterbi decoding processes. As a result, conventionally, there has been a problem that the determination time of the data speed becomes long.

On the other hand, according to this embodiment, the speed judgment based on the reproduction result is based on the data rate of 9.6 kbps,
It only needs to be performed for 19.6 kbps. Thus, at worst, the data rate can be determined by performing the data reproduction twice. Specifically, the data rate can be determined by one data repetition process and two Viterbi decoding processes.

As a result, according to the present embodiment, the data time determination time can be reduced as compared with the prior art.

(2) Further, according to this embodiment, the majority is used as the threshold value in the speed determination based on the ratio. Therefore, even when a data error occurs, the data speeds of 2.4 kbps and 4.8 kbps are maintained. In addition to accurate determination, even when the data rate of the received data is 9.6 kbps or 19.2 kbps, it is possible to prevent erroneous determination of 2.4 kbps or 4.8 kbps.

(3) Further, according to this embodiment,
The speed judgment based on the ratio is determined based on the data speed of 2.4 kbps,
Since the determination is performed only for 4.8 kbps, the accuracy of the speed determination can be improved.

That is, a high data rate requires a small number of samples (number of divisions) for taking a majority decision. Therefore, if the speed determination based on the ratio is applied to the determination of the data speed, the determination accuracy decreases.

On the other hand, a low data rate requires a large number of samples to take a majority decision. Therefore, when the speed determination based on the ratio is applied to the determination of the data speed, the determination accuracy can be improved.

Therefore, in the configuration in which the rate determination based on the ratio is applied to the determination of the low data rate as in this embodiment, the accuracy of this determination can be increased.

(4) According to this embodiment, when dividing data for one frame of the received data in the speed judgment based on the ratio, the binary judgment of the received data is performed and the judgment result for one frame is obtained. Is divided, so that the accuracy of the speed determination can be improved. This is because the waveform of the received data can be shaped by the binary determination.

[Other Embodiments] One embodiment of the present invention has been described above, but the present invention is not limited to the above-described embodiment.

(1) First, in the above embodiment, the case where the data speed of 9.6 kbps is determined by the speed determination based on the reproduction result has been described. However, in the present invention, this may be determined by the speed determination based on the ratio. In this case, the majority is 2.

(2) In the above embodiment, the case where the data rate of 4.8 kbps is determined by the rate determination based on the ratio has been described. However, in the present invention, this may be determined by the speed determination based on the reproduction result.

(3) In the above embodiment, the case where the speed judgment based on the ratio and the speed judgment based on the reproduction result are used together has been described. However, the present invention provides a data rate of 2.4.
If there are only three of kbps, 4.8 kbps, and 9.6 kbps, in other words, if the data rates before conversion are all lower than the data rates after conversion, only the rate determination based on the ratio may be used. . According to such a configuration, there is an advantage that the data buffer unit 202 can be omitted.

(4) In the above embodiment, the case where the threshold value of the speed determination based on the ratio is set to a majority is described. However, according to the present invention, the threshold value may be set to a value smaller than a majority within a range permitted by the determination accuracy.

(5) Further, in the above-described embodiment, the case where the received data is divided and the data of one frame is divided in the speed judgment based on the ratio has been described. However, according to the present invention, data for a plurality of frames may be divided for each frame.

In this case, the ratio of the same divided portion of the data pattern may be obtained for a plurality of frames as a whole, or may be obtained for each frame, and the sum of the calculated ratios for the plurality of frames may be divided by the number of frames. The averaging may be performed.

In the former configuration, even when the data speed before the speed conversion is the same as the data speed after the speed conversion, there is an advantage that the speed determination based on the ratio can be applied. In the previous example, the data rate of the baseband is 19.2 kb.
For ps, the speed determination based on the ratio can be applied.

(6) In the above embodiment, a case has been described where the present invention is applied to a CDMA receiver that restores the frame structure obtained by the data repetition processing to the original by the data accumulation processing. However, the present invention can also be applied to a CDMA receiver that restores the frame structure by data thinning processing.

(7) In the above embodiment, the block inserted into the frame after the speed conversion is composed of data obtained by rearranging the data included in the frame before the speed conversion according to a predetermined rule. The case where blocks are used has been described. However, the present invention may use a block composed of data included in a frame before the speed conversion.

In other words, in the above embodiment, a case has been described where the present invention is applied to a CDMA receiver that receives audio data subjected to block interleaving processing. However, the present invention can also be applied to a CDMA receiver that receives audio data not subjected to this processing.

(8) In the above embodiment, a case has been described in which the present invention is applied to a CDMA receiver of a mobile station constituting a digital cellular type portable telephone system.
However, the present invention can be applied to a receiver of a communication system other than such a communication system.

That is, according to the present invention, data transmitted in a state where the data rate is converted from the original rate to the predetermined rate, and the data rate before the rate conversion is a plurality of the predetermined data rates. This is for receiving data whose type is unknown, and the received data is
The frame after the speed conversion has a structure in which predetermined blocks are repeatedly inserted by the number corresponding to the speed conversion ratio, and the block arranges data included in the frame before the speed conversion or the data according to a predetermined rule. The present invention can be applied to a general data receiving apparatus including data obtained by replacement.

(9) In addition, it goes without saying that the present invention can be variously modified and implemented without departing from the scope of the invention.

[0131]

As described in detail above, according to the present invention,
One or more frames of the received data are equally divided by the number corresponding to the speed conversion ratio for each frame, and among the plurality of divisions obtained by this division, the division having the same data pattern is determined in advance. It is determined whether or not the received data exists by the ratio, and the data speed before the speed conversion of the received data is determined based on the determination result. Therefore, the data time determination time can be reduced.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a configuration of an embodiment of the present invention.

FIG. 2 is a block diagram showing a configuration of a CDMA transmitter for a traffic channel of a base station in a digital cellular mobile phone system.

FIG. 3 is a signal waveform diagram showing a frame structure after speed conversion.

FIG. 4 is a signal waveform diagram showing a frame structure when a data error is received.

[Explanation of symbols]

 Reference numeral 201: de-interleave unit 202: data buffer unit 203: data accumulation unit 204: Viterbi decoding unit 205: binary judgment unit 206: judgment result storage unit 207: majority decision judgment unit 208: speed judgment unit

Claims (14)

(57) [Claims] Claims 1. Data transmitted in a state where a data rate is converted from an original rate to a predetermined rate,
Receiving data that does not know which data rate before the speed conversion is any of a plurality of predetermined data rates,
The data rate before the speed conversion of the received data is to be determined.The received data has a structure in which predetermined blocks are repeatedly inserted by the number according to the speed conversion ratio in the frame after the speed conversion, The block, in a data rate determination device consisting of data obtained by rearranging data included in a frame before rate conversion or this data according to a predetermined rule, wherein the data rate of the received data before rate conversion is a certain rate. Assuming that the data corresponding to one or a plurality of frames of the received data is equally divided for each frame by a number corresponding to a ratio between the assumed speed and the data speed after the speed conversion, and a data pattern corresponding to the number of all divided portions Ratio rate determining means for determining the data rate of the received data before the rate conversion based on the ratio of the number of the same divided sections. Data rate determination apparatus characterized. 2. The data processing apparatus according to claim 1, wherein the ratio speed determining unit determines that the data speed of the received data before the speed conversion is the assumed speed when a majority of the same divisions of the data pattern exists. 2. The data rate determination device according to claim 1, wherein: 3. The method according to claim 2, wherein said ratio speed determining means sets a value of the received data to 1 for each bit of the received data.
Binary determination means for determining whether the received data is zero, determination result storage means for storing determination results for one or a plurality of frames of the binary determination means, and a data rate before the rate conversion of the received data is assumed to be a certain rate. Then, the determination results for one or a plurality of frames stored in the determination result storage means are equally divided for each frame by the number corresponding to the ratio between the assumed speed and the data speed after the speed conversion, and all divisions are performed. Ratio determining means for determining whether or not the ratio of the number of the same divided parts of the data pattern to the number of the parts is equal to or greater than a predetermined ratio; based on the determination result of the ratio determining means, 2. The data rate judging device according to claim 1, further comprising speed judging means for judging a data rate. 4. Assuming that the data speed of the received data before the speed conversion is a certain speed, and determining the data speed of the received data before the speed conversion based on a reproduction result of the received data according to the assumed speed. 2. The data speed judging device according to claim 1, further comprising a reproduction result speed judging means for performing the reproduction. 5. The ratio speed determining unit is configured to determine a lower data speed among the plurality of data speeds, and the reproduction result speed determining unit is configured to determine a higher speed among the plurality of data speeds. 5. The data rate determining apparatus according to claim 4 , wherein the data rate is determined. 6. The data rate judging device according to claim 1, wherein the received data is convolutionally encoded. 7. In a code division multiple access communication system for transmitting data encoded at a variable rate from a base station to a mobile station, the system is used as a data rate determination device for a receiver of the mobile station. The data rate determination device according to claim 1, wherein 8. Data sent in a state where a data rate is converted from an original rate to a predetermined rate,
It is to receive data for which it is not known whether the data rate before the speed conversion is one of a plurality of predetermined data rates, and the received data is a frame after the speed conversion, and a predetermined block has a speed conversion ratio. The block has a structure repeatedly inserted by the number according to the above, wherein the block is a data receiving device comprising data included in a frame before rate conversion or data obtained by rearranging this data according to a predetermined rule, Data rate determining means for determining a data rate of the received data before rate conversion based on the received data; and reproducing the original data from the received data based on the data rate determined by the data rate determining means. A data reproducing unit, wherein the data speed determining unit determines a data speed of the received data before speed conversion. Assuming the speed, the data for one or more frames of the received data is equally divided for each frame by a number corresponding to the ratio between the assumed speed and the data speed after the speed conversion, and A data receiving apparatus, comprising: a ratio speed determining unit that determines a data speed of the received data before the speed conversion based on a ratio of the number of division units having the same data pattern. 9. The ratio speed determining means is configured to determine that the data speed of the received data before the speed conversion is the assumed speed when a majority of the same divisions of the data pattern exist. 9. The data receiving device according to claim 8, wherein: 10. The binary rate determining means, for each bit of the received data, determines whether the value of the received data is 1 or 0, and for one or more frames of the binary determining means. Determination result storage means for storing the determination result of the above, assuming that the data speed of the received data before the speed conversion is a certain speed, the number of the determination results by the number according to the ratio between this assumed speed and the data speed after the speed conversion The determination result for one or more frames stored in the storage unit is equally divided for each frame, and whether or not the ratio of the number of the same divisions of the data pattern to the number of all the divisions is equal to or greater than a predetermined ratio 9. A data determining apparatus according to claim 8, further comprising: a rate determining means for determining a data rate of the received data based on a determination result of the rate determining means. Receiver. 11. Assuming that the data rate of the received data before the rate conversion is a certain rate, and based on a result of the data reproduction performed by the data reproducing means in accordance with the assumed rate, the data rate of the received data is determined. 9. The data receiving apparatus according to claim 8, further comprising a reproduction result speed judging means for judging a data speed before speed conversion. 12. The ratio speed determining unit is configured to determine a lower data speed among the plurality of data speeds, and the reproduction result speed determining unit is configured to determine a higher speed among the plurality of data speeds. The data receiving device according to claim 11, wherein the data rate is determined. 13. The data receiving apparatus according to claim 8, wherein said received data is subjected to convolutional encoding, and said reproducing means includes Viterbi decoding means for Viterbi decoding the received data. 14. A communication system according to claim 8, wherein said base station is used as a receiver of said mobile station in a code division multiple access communication system for transmitting data encoded at a variable rate from said base station to said mobile station. Data receiving device.