JP3335337B2 - Receiver - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a large amount of information such as audio data and computer data, moving images, and the like.
The present invention relates to a communication receiving apparatus that can efficiently handle information signals of different transmission rates such as real-time and large-capacity high-speed data.

[0002]

2. Description of the Related Art To perform multimedia communication,
The same communication from data that can be communicated at a low transmission rate of about several tens of kb / s (bits / second), such as audio data, to data with a high transmission rate of several hundred kb / s or more, such as moving images. It must be handled by the system. Recently, CDMA has become a system that can multiplex users using the same band.
(Code Division Multiple Access) communication systems are receiving attention. ITU (International Telecommunications Union)
The adoption of this CDMA communication system has also been almost decided in IMT2000, which is being studied in this paper.

[0003] The CDMA communication system uses a spread-spectrum communication technique in which a transmission band is widened by multiplying each symbol by a high-speed spreading code. In CDMA communication, all users can use a common band. Each user can be separated on the receiving side by the difference of the spreading code used on the transmitting side.

[0004] There are two methods for transmitting at various transmission rates using the CDMA communication system. One is a method in which a certain user performs communication using a plurality of spreading codes adaptively. Thereby, even if the transmission rate for each spreading code is fixed, various transmission rates can be realized by changing the multiplex number. The other is a method of changing the number of data within a certain time (frame) by using one spreading sequence. This includes a method of repeatedly communicating the same data with a plurality of symbols and a method of providing a gap in a frame. In any case, it is necessary to determine the transmission rate using some means in the receiving device.

Conventionally, in order to determine a transmission rate, a transmission rate information signal is added to a preamble signal prepared in a frame of an information signal at the time of transmission, or a control channel is provided. Or is added. Further, there is a blind rate determination method for estimating a transmission rate from an information signal transmitted at a variable rate without a transmission rate information signal without adding transmission rate information to a pilot signal, a preamble signal, or the like. For example Japanese Patent No. 297269 Patent 4, communication system it is possible to determine the transmission rate without information transmission rate on the receiving side in method of communicating repeatedly in multiple symbols of the same data in a certain time (frame) is proposed Have been.

[0006] Here, respectively an example of a schematic configuration of a transmission rate determination unit in an example and a receiving apparatus of a schematic configuration of a transmitting apparatus of the Patent No. 297269 4 No. 7 and 8. The information modulation here is BPSK modulation. Also, 2
A case is shown in which four types of transmission rates are determined by switching between types of random code sequences PN1 and PN2.

[0007] In FIG. 7, a decoding tail bit adding unit 702 adds several bits of 0 to the end of a frame of an information signal 701 that can take a plurality of transmission rates, according to the constraint length during encoding processing. Next, the encoding processing unit 703
After the convolutional encoding is performed in
In step 4, information modulation processing such as BPSK is performed. Thereafter, symbol repetition processing similar to that described above is performed, and information signals of all transmission rates are unified to a reference transmission rate. After that, an interleaving section 706 performs an interleaving process for the purpose of reducing burst errors of the information signal.

Next, a spread code generator 70 capable of generating at least two types of random code sequences on the same path.
Switching means 708 for switching and outputting the random code sequence generated in step 7 according to a switching pattern corresponding to the transmission rate
Is multiplied by the spreading code sequence output from After that, the signal is converted into an analog signal by the wireless unit 709 and becomes a transmission signal 710. The transmission signal is transmitted at one of various transmission rates at any stage of the baseband processing or in the radio unit 710.
In order to equalize the energy per bit, a process of changing the instantaneous average output power according to each transmission rate is performed.

On the other hand, in the receiver shown in FIG. 8, a received signal 801 is divided into two. Each path has a symbol period that is the maximum transmission rate per spreading code,
Two types of random code sequences PN1 and PN used on the transmission side
Despreading code generator 804a, 8
04b. Each multiplied signal is used for data demodulation processing of a receiver such as information demodulation and is input to a transmission rate determination unit 810. Here, the data demodulation processing is omitted, and only the processing related to the transmission rate determination is shown. The two multiplied signals that have entered the transmission rate determination unit 810 are output by each instantaneous power calculation unit to 1
An instantaneous power value for the output of the I and Q phases of the symbol period that becomes the maximum transmission rate per spreading code is obtained. In the transmission rate determination, a value obtained by quantizing the instantaneous power value by several bits may be used.

Next, the signal switching unit 805 distributes the signals in accordance with the switching patterns corresponding to all the transmission rates on the transmitting side, and performs switching processing for each.
Thereafter, the integrators 806a to 806d are provided for each transmission rate.
Thus, an integration process of a common time is performed at all transmission rates. The outputs are compared by a comparator 808, and the transmission rate having the largest value is determined as the transmitted transmission rate, and transmitted as a transmission rate information signal 809 to an information demodulation unit or the like.

Here, an example of a schematic configuration of another transmitting apparatus and an example of a schematic configuration of a transmission rate determining unit in the receiving apparatus are shown in FIGS. 9 and 10, respectively. Again, the information modulation is B
PSK modulation is used. In addition, four types of random code sequences P
A case is shown in which four types of transmission rates are determined by switching between N1, PN2, PN3, and PN4.

In FIG. 9, a decoding tail bit adding section 902 adds several bits of 0 to the end of a frame of an information signal 901 which can take a plurality of transmission rates, according to the constraint length at the time of encoding processing. Next, the encoding processing unit 903
After the convolutional coding is performed in
In step 4, information modulation processing such as BPSK is performed. Thereafter, symbol repetition processing similar to that described above is performed, and information signals of all transmission rates are unified to a reference transmission rate. Thereafter, the interleaving section 906 performs an interleaving process for the purpose of reducing burst errors of the information signal.

Next, four types of random code sequences PN1,
By inputting a spreading sequence switching signal 907 according to the transmission rate to a spreading code generator 908 capable of generating one of PN2, PN3, and PN4, PN1, PN2, P
One of N3 and PN4 is multiplied by the output of the interleave. After that, the signal is converted into an analog signal by the wireless unit 909 and becomes a transmission signal 910. The transmission signal is subjected to a process of changing the average output power according to each transmission rate in any stage of the baseband processing or in the radio unit 909 in order to equalize the energy per bit at various transmission rates. .

On the other hand, in the receiver shown in FIG. 10, received signal 1001 is divided into four. In each path, for each symbol period of each transmission rate, 4
Types of random code sequences PN1, PN2, PN3, PN
4 to generate despreading code generators 1004a to 1004a to
1004d. Each multiplied signal is used for data demodulation processing of a receiver such as information demodulation,
It is input to the transmission rate determination unit 1010. Here, the data demodulation processing is omitted, and only the processing related to the transmission rate determination is shown.

[0015] If the 4
For each of the two multiplied signals, the respective instantaneous power calculators determine the instantaneous power according to the symbol period of each transmission rate. Then, for each transmission rate, the integrator 100
In 6a to 1006d, integration processing in a unit of time common to all transmission rates is performed. That is, the number of symbols subjected to integration processing differs for each transmission rate. The outputs are compared by a comparator 1008, and the transmission rate showing the largest value is determined as the transmitted transmission rate, and transmitted as a transmission rate information signal 1009 to an information demodulation unit or the like.

[0016]

In the above transmission system, when transmitting information at various transmission rates, it is necessary to equalize the energy per bit at each transmission rate. As shown in FIG. 4, in the case of intermittent transmission, the average power in the sound interval is constant regardless of the transmission rate, and the intermittent interval changes. However, in the case of continuous transmission in which the same data is repeatedly communicated with a plurality of symbols within a certain fixed time (frame), the instantaneous average power changes according to the transmission rate, as shown in FIG. Therefore, in the continuous transmission system, the energy at the time of dividing by a certain unit time changes according to the transmission rate actually transmitted. Therefore, when the determined transmission rate using the determination method of Patent No. 297269 No. 4 described above, there is a problem that the transmission rate decision error rate becomes different between the respective transmission rate.

FIG. 11 shows an example of calculation by a computer of a transmission rate judgment error rate characteristic according to a conventional example. As shown
The transmission rate error rates between the transmission rates at the same Eb / N0 are greatly different. For example, Eb / N0 = 10
In the case of (dB), the difference between the transmission rate determination error rates is about 100 times at the maximum. Therefore, when the conventional determination method is adopted, there is a problem that the transmission rate error rate increases as the transmission rate decreases, and the error rate of the received signal based on the transmission rate determination error also increases.

Accordingly, the present invention provides the same transmission rate determination error rate for all transmission rates by assigning different weights to the integration result of the transmission rate determination unit for each circuit according to each transmission rate. It is an object of the present invention to provide a receiving apparatus capable of performing variable rate data transmission capable of determining a blind transmission rate.

Further, according to the present invention, the transmission result judgment error rate for each transmission rate can be controlled in accordance with the situation by giving different weights to the integration result of the transmission rate judgment unit for each circuit independent of each transmission rate. It is another object of the present invention to provide a receiving apparatus capable of performing variable rate data transmission in which a receiving side can determine a blind transmission rate.

[0020]

In order to achieve the above object, a receiving apparatus of the present invention receives a spread-spectrum received signal, performs a despreading process corresponding to each transmission rate, and performs a despreading process corresponding to each transmission rate. Quantization value output means for outputting a plurality of quantization values corresponding to the transmission rate, weighting means for multiplying the output from the quantization value output means by a larger weight as the transmission rate is lower, and the weighting means And a transmission rate output means for outputting a transmission rate signal by comparing the outputs of the above.

According to another aspect of the present invention, there is provided a receiving apparatus according to the present invention, wherein the quantized value output means receives a spread-spectrum received signal, and has the same code speed and the same code length but different from each other. A plurality of correlators configured to perform despreading processing with a despreading code, a plurality of selection means for selecting output signals of the plurality of correlators, according to respective transmission rates, and a plurality of selection means. And a plurality of integrators each integrating the output signal in a common time unit.

Still further, in order to achieve the above object, in the receiving apparatus according to the present invention, the quantized value output means receives a spread-spectrum received signal and outputs a code corresponding to a transmission rate at the same code rate. A plurality of correlators configured to perform despreading processing with despreading codes having mutually different lengths, and a plurality of integrators each integrating output signals of the plurality of correlators in a common time unit. And

[0023]

DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of a receiving apparatus according to the present invention will be described in detail with reference to the accompanying drawings. FIG. 1 shows the configuration of the transmission rate determining unit of the receiving apparatus according to the present invention. As the received signal 101, it is assumed that the output from the conventional transmitting device as shown in FIG. 8 is input through a wireless transmission section. The information modulation here is BPSK modulation, and two types of random code sequences P
A case is shown in which the transmission rate transmitted from four types of transmission rates is determined by switching between N1 and PN2. In the receiving device, the received signal 101 is divided into two, and is multiplied by despreading code generators 103a and 103b that generate one of two types of random code sequences PN1 and PN2 used on the transmitting device side in each path. Is done.

Each of the multiplied signals is converted to an instantaneous power
4a and 104b. Here, an instantaneous power value for each chip is obtained and output from the input signal. Here, since the received signal is BPSK-modulated, if the phase is compensated, it is sent to the signal switching unit 105 without any particular processing. However, when phase compensation is not performed, or in the case of QPSK modulation or the like, instantaneous power is calculated from IQ components. Further, instead of outputting the instantaneous power as it is, it is also possible to output another value according to the instantaneous power by performing quantization or the like.

Next, in the signal switching section 105, P
The N1 side signal 112 and the PN2 side signal 113 are distributed into four so as to correspond to all assumed transmission rates, and are output while switching in common time units according to the respective transmission rates. The output result is the integrator 106a, 10
The integration for a certain time is performed in each of 6b, 106c, and 106d. The integration time here is common to all transmission rate circuits. The weight control unit 107
Are multiplied by different weights for each transmission rate. Table 2 in FIG.
Shows a numerical example of the weight. The weighting controls the transmission rate determination error rate for each transmission rate. The larger the value of this weight, the lower the transmission rate determination error rate for that transmission rate. The weighted signal enters the comparator 108, and the comparator outputs the transmission rate having the maximum value as the transmission rate information signal 110. By this transmission rate information signal 110, despreading processing, information demodulation, deinterleaving,
Processing such as decoding is performed at the determined transmission rate.

FIG. 2 shows an example of the configuration of the signal switching section 203 for the PN1 side signal 201 and the PN2 side signal 202 after multiplication by the despreading code in the receiving apparatus. This figure details the signal switching unit 105 shown in FIG. The PN1 side signal 201 and the PN2 side signal 202 are all the transmission rate switches 204, 205, 206, 2
07. However, in the example of Table 1, X (b
Since the switch corresponding to (/ s) does not require the PN2 side signal 202, the PN2 side signal 202 may be divided into three. In the switch, a switching process is performed by a signal from the switching signal generator 208.

The switching signal generator is, for example, as shown in FIG.
Reference table values for each transmission rate as shown in Table 1 and a switching timing signal 209 for each symbol of the maximum transmission rate.
Is output. The switching timing signal is not shown in FIG. 1 because it may be generated in the transmission rate determining unit depending on the situation. The signal switched in this manner becomes the signal switching unit output signal a2
10, signal switching unit output signal b211, signal switching unit output signal c212, signal switching unit output signal d213
Is output to the integrator.

The signal switching unit output signal a210, the signal switching unit output signal b211 and the signal switching unit output signal c
212, the signal switching unit output signal d213 is, for example,
X (b / s) and x / 2 (b / s) shown in Table 1 of FIG.
s), x / 4 (b / s), and x / 8 (b / s).

Another embodiment of the receiving apparatus according to the present invention will be described in detail with reference to the accompanying drawings. FIG. 3 shows the configuration of the transmission rate determining unit of the receiving apparatus according to the present invention. As the received signal 101, it is assumed that the output from the conventional transmitting apparatus as shown in FIG. 9 is input through a wireless transmission section. The information modulation here is BPSK modulation. Also, a case is shown in which four types of transmission rates are determined by switching between four types of random code sequences PN1, PN2, PN3, and PN4.

In the receiving apparatus, the received signal 301 is divided into four, and four kinds of random code sequences PN1, PN2, PN3, PN4 used on the transmitting apparatus side in each path.
Despreading code generator 303a, 30
3b, 303c and 304c. Next, symbol time integration processing 3 corresponding to each transmission rate
05a, 305b, 305b, 305c, and 305d are performed. The signals after the multiplication and integration processing are input to the instantaneous power calculation units 304a, 304b, 304c, 304d.

Here, for the input signal, the instantaneous power for each symbol according to the transmission rate of each circuit is obtained and output. Here, since the received signal is BPSK-modulated, if phase compensation is performed, no special processing is performed, and the integrators 306a, 306b, and 306 are not processed.
c, 306d. However, when phase compensation is not performed, or in the case of QPSK modulation or the like, instantaneous power is calculated from IQ components. Also, instead of outputting the instantaneous power as it is, another value according to the instantaneous power can be output.

Integrators 306a, 306b, 306c, 3
In 06d, the integration for a fixed period of time common to all the integrators is performed. That is, the number of symbols subjected to integration processing differs for each transmission rate. The integration result is multiplied by different weights W1 to W4 for each transmission rate of the weight control unit 307. The weighting controls the transmission rate determination error rate for each transmission rate. The larger the value of the weight, the lower the transmission rate determination error rate. The signal after the weighting enters the comparator 308, where the transmission rate having the maximum value is output as the transmission rate information signal 310. With the transmission rate information signal 310, processing such as despreading processing, information demodulation, deinterleaving, and decoding according to the transmission rate is performed at the determined transmission rate.

FIG. 5 shows how the switching means 105 determines how the random code sequences PN1, 2
It is a figure showing an example of whether or not is selected. In this figure, the encoded information signal before spreading is shown on the left side of the figure, and the corresponding transmission signal is shown on the right side. Here, assuming that a reference transmission rate is X (b / s), a case is shown in which four types of transmission rates can be obtained as in the conventional case. It is also assumed that a preamble signal, a tail bit signal for decoding, and the like are components in the frame, but are not shown. As shown in Table 1 of FIG. 12, PN1 is selected when the value of the reference table is 0, and PN2 is selected when the value of the reference table is 1 or 1.

In the illustrated example, the transmission rate X (b
/ S) is spread only at PN1, but not at PN2. Therefore, in the case of X (b / s), 000
0 is the switching pattern. When the transmission rate is X / 2 (b / s), the switching pattern is 0101 as shown, and the same data is spread by 1 / X (sec.) In the order of PN1 and PN2.

When the transmission rate is X / 4 (b / s),
First, it is spread for 2 / X (sec.) At PN1 and then for 2 / X (sec.) At PN2. This X /
In the case of 4 (b / s), as in X / 2 (b / s), P
The data is the same while being spread by N1 and PN2. Finally, in the case of the rate X / 8 (b / s), PN1 up to 1 / X (sec.) Of X / 8 (sec.) Where the same data is repeated, and 2 / X (sec.) From 1 / X. .) At intervals P
N2, PN1, and PN2 are spread, and the last is 1 / X (se
c. )).

For example, when a received signal having a transmission rate of X / 4 is input, the instantaneous value of the peak of the power signal appearing at each output terminal of the switching means 105 is all the same if the despreading codes match. P / 4, 0 in case of mismatch
Becomes Therefore, when integrating this output value for a period of 8 / X (sec.), In an integrator having the same transmission rate, the peak value P / 4 is input in all periods, but the transmission rate is different. In the integrator, 8 / X
(P.4) only during a half of the period of (sec.)
Is entered. Therefore, if there is no noise, the output of the integrator having the same transmission rate has an output value twice as high as the output of the other integrators, and the transmission rate can be determined.

However, as shown, for example, 8 / X
(Sec.), When the transmission rate is determined, the total power (P) when X (b / s) is transmitted
Represents the power (P / P) when X / 8 (b / s) is transmitted.
8), and the output value of the integrator also has an eight-fold difference depending on the transmission rate. Therefore, a difference appears in the transmission rate determination error rate in the receiving device at the same Eb / N0.

FIG. 11 shows an example of calculation of a transmission rate judgment error rate characteristic by a computer according to a conventional example. As shown in the figure, it can be seen that the transmission rate error rates between the respective transmission rates at the same Eb / N0 are significantly different. For example, Eb / N0 = 10
In the case of (dB), the difference between the transmission rate determination error rates is about 100 times at the maximum. FIG. 6 shows a calculation example using a computer equivalent to that of FIG. 11 using the receiving apparatus of the present invention. In this case, it can be seen that the power is reduced by about 10 times at the maximum. As described above, the present invention changes the weight for each transmission rate in the transmission rate determination unit of the receiving device,
This is to reduce the difference in the transmission rate determination error rate.

For the weight, for example, a simulation for obtaining a decision error rate of each transmission rate by changing a weight value is repeated,
A weight value at which the determination error rate of each transmission rate becomes equal may be obtained. Further, an approximate expression representing the weight value obtained by the simulation may be obtained, and the weight value may be calculated by the approximate expression. For example, the following Expression 1 or Expression 2 can be adopted as the approximate expression.

[Expression 1] W = 1− (constant) × (transmission rate corresponding to the weight) [Expression 2] W = (1− (constant 1) × (transmission rate corresponding to the weight)) × constant 2 Table 2 in FIG. 12 shows that the above equation 1
Is the weight value obtained by Equation 1 can be transformed into Equation 3 and Equation 2 can be transformed into Equation 4. [Equation 3] W = 1− (constant) / (diffusivity) [Equation 4] W = (1− (constant 1) / (diffusivity)) × constant 2 In this case, Table 2 in FIG. Assuming that the denominator is the spreading factor, a constant value of 32 may be used as the weight value obtained by the above equation 3.

[0041]

As described above, since the receiving apparatus is provided with the transmission rate determining means of the present invention, the transmission side can transmit data without adding transmission rate information to a pilot signal, a preamble signal, or the like on the transmission side. It is possible to determine the rate and to determine the transmission rate at the same transmission rate determination error rate for all transmission rates. Further, by calculating the weight value by the calculation formula, there is an excellent effect that the weight value of the weight control unit for each transmission rate can be set uniquely, not for each transmission rate.

[Brief description of the drawings]

FIG. 1 is a block diagram illustrating an example of a configuration of a transmission rate determination unit in an embodiment of a receiving device of the present invention.

FIG. 2 is a block diagram illustrating an example of a configuration of a signal switching unit in the configuration of the transmission rate determination unit illustrated in FIG. 1;

FIG. 3 is a block diagram showing a configuration example of another embodiment of the receiving device of the present invention.

FIG. 4 is a state diagram showing a general output signal at the time of transmission in spread spectrum communication.

5 is a diagram illustrating an example of a frame configuration of a signal before spreading and a transmission signal after spreading in the spread spectrum transmitter illustrated in FIG. 7;

FIG. 6 is a diagram showing transmission rate determination error rate characteristics in the receiving apparatus shown in FIG. 1 of the present invention.

FIG. 7 is a block diagram illustrating a configuration example of a transmission apparatus of the conventional spread spectrum communication.

FIG. 8 is a block diagram illustrating a configuration example of a transmission rate determination unit of a conventional receiving device.

FIG. 9 is a diagram illustrating a conventional transmitter for spread spectrum communication.
It is a block diagram which shows the example of a structure different from.

FIG. 10 is a block diagram illustrating a configuration example of a transmission rate determination unit of a conventional receiving device.

11 is a diagram illustrating a transmission rate determination error rate characteristic of the conventional receiver illustrated in FIG. 8;

FIG. 12 is an explanatory diagram showing a reference table for switching corresponding to a transmission rate and an example of a weight value for each transmission rate.

[Explanation of symbols]

101, 301, 801, 1001 Received signals 102, 302, 709, 802, 909, 1002
Radio units 103a, 103b, 303, 803a, 803b, 1
003 despreading code generators 104a, 104b, 304a, 304b, 304c,
304d Instant power calculator 804a, 804b Instant power calculator 1005a, 1005b, 1005c, 1005d Instant power calculator 105, 203, 805 Signal switching unit 106a, 106b, 106c, 106d Integrators 305a, 305b, 305c, 305d Integrator 306a , 306b, 306c, 306d Integrators 806a, 806b, 806c, 806d Integrators 1005a, 1005b, 1005c, 1005d Integrators 1006a, 1006b, 1006c, 1006d Integrators 107, 307 Weight control units 108, 308, 808, 1008 110, 310, 809, 1009 Transmission rate information signal 111, 311, 810, 1010 Transmission rate determination unit 112, 201 PN1 side signal 113, 202 PN2 side signal 2 4, 205, 206, 207 Switcher 208 Switching signal generator 209 Switching timing signal 210 Signal switching unit output signal a 211 Signal switching unit output signal b 212 Signal switching unit output signal c 213 Signal switching unit output signal d 701, 901 Information Signal 702, 902 Decoding tail bit adding section 703, 903 Encoding processing section 704, 904 Information modulation section 705, 905 Symbol repetition section 706, 906 Interleaving section 707, 908 Spread code generator 708 Switching means 710, 910 Transmission signal

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-5-102943 (JP, A) JP-A-9-8769 (JP, A) JP-A-7-283758 (JP, A) 506763 (JP, A) Table 6-501349 (JP, A) Table 10-507333 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) H04B 1/707 H04L 1 / 00

Claims (4)

(57) [Claims] At a transmitting side, information of all transmission rates is provided.
Signal is unified to the reference transmission rate, spectrum
Spread and energy per bit is equal
Multiple transmission rates transmitted with output power control
Receiver in a system for transmitting information signals
And a quantization value output means for receiving the spread spectrum received signal, performing a despreading process corresponding to each transmission rate, and outputting a plurality of quantization values corresponding to each transmission rate. A weighting means for multiplying the output from the quantization value output means by a larger weight as the transmission rate is lower; and a transmission rate output means for outputting a transmission rate signal by comparing the output of the weighting means. A receiving device comprising: 2. The apparatus according to claim 1, wherein said quantized value output means receives a spread-spectrum received signal and performs a plurality of despreading processes at the same code rate and with different despread codes having the same code length. A correlator, a plurality of selecting means for selecting output signals of the plurality of correlators in accordance with respective transmission rates, and a plurality of integrators each integrating the output signals of the plurality of selecting means in a common time unit. The receiving device according to claim 1, comprising: 3. The quantized value output means is configured to receive a spread-spectrum received signal and perform despreading processing at the same code rate and with mutually different despread codes having a code length corresponding to a transmission rate. 2. The receiving apparatus according to claim 1, comprising: a plurality of correlators thus obtained; and a plurality of integrators each integrating output signals of the plurality of correlators in a common time unit. 4. When the weight is W, W = 1− (constant) ×
(The transmission rate corresponding to the weight) or W = (1-
2. The receiving apparatus according to claim 1, wherein (constant 1) × (transmission rate corresponding to the weight)) × constant 2.