JP3300324B2 - Signal to noise interference power ratio estimator - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a mobile radio communication system, particularly, a code division multiplexing communication system (CDMA), in which the same user multiplexes and transmits a plurality of channels. Signal-to-noise interference power, which is used for variable transmission control of the number of multiplex channels and calculates the ratio of the power of a desired signal component included in a received signal to the power of other noise interference signal components The present invention relates to a ratio estimating device.

[0002]

2. Description of the Related Art Conventionally, such a technique is described in, for example, literature: "Study of SIR Measurement Method in Adaptive Transmission Power Control of B-330 DS-CDMA" by Kiyoo et al., 1996.
IEICE Communications Society Conference, p. 331
And the like. In CDMA, each communication station shares and uses the same frequency band, and a transmission signal from each communication station is identified and received by a spreading code uniquely assigned to each communication station. In this case, in order to make the communication quality of each communication station the same and fair, and to improve the frequency use efficiency of transmission, the noise (N) of the power (S) of the signal component received from the desired station and the noise signal (N) can be improved. Noise interference signal component (N + I) combined with interference signal (I) received from the station
It is necessary that the ratio [SNIR = S / (N + I): signal-to-noise-interference power ratio] is constant and the same at each communication station. In order to achieve such an object, each communication station controls transmission power. The above document proposes an SNIR estimator used for the transmission power control.

FIG. 6 is a block diagram showing a conventional signal to noise and interference power ratio estimating apparatus. A transmission signal from the partner station is received by a transmission / reception antenna 601, converted into a baseband signal in a spread band by a high frequency circuit 602, and output to a reception channel 603. Spreading demodulation (despreading) by multiplying the spread code signal by the despreading circuit 604 of the reception channel 603
Then, a data-modulated signal from the partner station is output. At this time, the signal is separated into a preceding wave and one or a plurality of delayed waves and output to the RAKE combining circuit 605. A pilot signal, which is a known signal, is inserted into the transmission signal at a fixed period, for example, in units of slots, in a plurality of symbols. This slot constitutes a frame with a plurality of slots and a packet which is a unit of transmission with a plurality of frames.

[0004] A signal received by a mobile communication station not only fluctuates in reception signal level due to fading but also fluctuates in phase with respect to a carrier. In other words, the I and Q components with respect to the carrier phase vary independently. In this specification, the level fluctuation and the phase fluctuation are collectively referred to as fading distortion. The fading distortion calculation circuit 608 estimates the fading distortion for each of the arriving waves by calculating the average value of the received signal level and the carrier phase in each of the plurality of symbol sections in which the pilot signal is inserted for each of the arriving waves. .

A RAKE combining circuit 605 equalizes the delay times of a plurality of arriving waves, corrects the fading distortion of a plurality of arriving waves using the calculated fading distortion estimation value, and performs a combining process. Output the composite signal. The in-slot signal power calculation circuit 606 includes a RAKE combining circuit 605.
The power of the in-slot signal component is estimated based on the RAKE composite signal output from. More specifically, the average value of the signal level of the RAKE combined signal (average of fading envelope) for data modulation signals of a plurality of symbol data in the middle of one slot section including the pilot signal section or in the entire section of one slot. Value), and the square of the average value is estimated to be the power of the in-slot signal component.

[0006] In-slot noise interference power calculation circuit 607
From the power of this estimated in-slot signal component,
By calculating the variance of the RAKE combined signal, the power of the intra-slot noise interference signal component is estimated. More specifically, a reference signal of a pilot signal whose amplitude value is the square root of the power of the estimated in-slot signal component at the symbol phase of the known pilot signal on the I and Q phase planes with respect to the carrier phase. Is calculated, the square of the length of the difference vector from the amplitude phase point of the RAKE combined signal is calculated, and this is averaged for a plurality of symbols of the pilot signal, and the average value is estimated for the power of the noise interference signal component in the slot. Value.

The power of the in-slot noise interference signal component is further calculated as follows:
2, a long-term average noise interference power for a plurality of slots is calculated and used as the noise interference power. Since the power of the noise interference signal component can be calculated only in a known signal section such as a pilot signal, the number of symbols for estimating the power of the noise interference signal component is small, and statistically accurate estimation cannot be performed. . Therefore, the average value is calculated over a plurality of slots. On the other hand, regarding the power of the desired signal component, it is necessary to observe the instantaneous power fluctuation of the reception slot, so the intra-slot signal power calculation circuit 606 estimates within one slot. The SNIR calculation circuit 614 estimates the signal-to-noise-interference power ratio based on the ratio between the power of the desired signal component and the power of the noise interference signal component estimated in this manner.

[0008]

By the way, in recent multimedia communication, various services, data of various media, data requiring a large transmission capacity, and the like are transmitted over a transmission path of the same band. In addition, there is a demand for a technique that allows one user to simultaneously and efficiently transmit a plurality of data. Therefore, a plurality of channels are multiplexed using different spreading codes and transmitted, and the number of multiplexed channels is changed. Further, the modulation multi-level number of each multiplex channel is calculated for at least one of spreading modulation and data modulation. It is necessary to transmit while adaptively variably controlling according to the signal-to-noise-interference power ratio.

However, in the conventional signal-to-noise-interference power ratio estimating apparatus, since the number of samples for which the noise-interference signal component can be calculated in one slot is small, an accurate signal-to-noise-interference-power ratio (SNIR) is estimated. It was difficult to do.
If the power of the noise interference signal component is averaged over a long period of time, the accuracy will be improved. However, it is not possible to immediately respond to a change in interference between users due to an increase or decrease in traffic. Also in the fading distortion calculation circuit, since estimation is performed using a pilot signal, accurate estimation is difficult.
Good fading correction cannot be performed, which also makes it difficult to accurately estimate the signal-to-noise-interference power ratio.

SUMMARY OF THE INVENTION The present invention has been devised to solve the above-mentioned problems. In a multimedia communication system or the like in which one user multiplexes and transmits a plurality of channels, signal-to-noise interference with high accuracy is easily achieved. It is an object of the present invention to provide a signal-to-noise-interference power ratio estimating apparatus capable of estimating a power ratio.

[0011]

In order to achieve the above object, according to the first aspect of the present invention, a channel including a known signal transmitted at a predetermined cycle interval from a partner station is provided. A signal-to-noise-interference power ratio estimating apparatus for receiving a spread modulated signal obtained by multiplexing the signals, and estimating a ratio between the power of the desired signal component and the power of the noise interference signal component. For the channels, based on the power of the desired signal component calculated for each channel of the plurality of channels and the power of the noise interference signal component calculated for each channel of the plurality of channels, By calculating the ratio between the power of the desired signal component and the power of the noise interference signal component, the ratio between the power of the desired signal component and the power of the noise interference signal component is calculated. It is intended to. By calculating the ratio between the power of the desired signal component and the power of the noise interference signal component, which has been averaged for a plurality of channels, the number of symbols of the signal to be calculated can be substantially doubled by the number of channels, The estimated value of the signal-to-noise-interference power ratio can be easily and accurately made.

According to a second aspect of the present invention, in the signal-to-noise interference power ratio estimating apparatus according to the first aspect,
For each of the plurality of channels, the power of the desired signal component is calculated for each of the plurality of channels based on a despread signal of each of the plurality of channels or a signal obtained by fading-correcting the despread signal. A plurality of signal power calculation circuits, a signal power average value calculation circuit for calculating an average value of outputs of the plurality of signal power calculation circuits, and, for the plurality of channels, despread each channel of the plurality of channels. A signal obtained by fading-correcting the signal, and based on the output of the signal power average value calculation circuit, calculates the power of the noise interference signal component for each of the plurality of channels, a plurality of noise interference power calculation circuits, Based on the output of the signal power average value calculation circuit and the outputs of the plurality of noise interference power calculation circuits, Treated averaged with respect to the channel, but with a signal-to-noise interference ratio average value calculation circuit for calculating the ratio of the power of the power and noise interference signal component of the desired signal component. By calculating the ratio between the power of the desired signal component and the power of the noise interference signal component averaged for a plurality of channels, it is possible to easily and accurately calculate the estimated value of the signal-to-noise interference power ratio. .

According to a third aspect of the present invention, in the signal-to-noise-interference power ratio estimating apparatus according to the first aspect, for each of the plurality of channels, a signal obtained by despreading each of the plurality of channels or the despread signal is used. A plurality of signal power calculation circuits for calculating the power of the desired signal component for each of the plurality of channels based on the signal obtained by fading-correcting the despread signal; and for the plurality of channels, the plurality of channels, respectively. A signal obtained by fading-correcting the despread signal of each channel, and the power of the noise interference signal component for each of the plurality of channels, based on the outputs of the plurality of signal power calculation circuits. A noise interference power calculation circuit, and a noise interference power average for calculating an average value of outputs of the plurality of noise interference power calculation circuits A calculation circuit, the plurality of signal power calculation circuits, and the power of the desired signal component and the noise interference signal component averaged with respect to the plurality of channels based on the output of the noise interference power average calculation circuit. And a signal-to-noise-interference power ratio average value calculating circuit for calculating a ratio with respect to the power. By calculating the ratio between the power of the desired signal component and the power of the noise interference signal component averaged for a plurality of channels, it is possible to easily and accurately calculate the estimated value of the signal-to-noise interference power ratio. .

According to a fourth aspect of the present invention, in the signal-to-noise interference power ratio estimating apparatus according to the first aspect, for each of the plurality of channels, a signal obtained by despreading each of the plurality of channels, A plurality of signal power calculation circuits for calculating the power of the desired signal component for each of the plurality of channels based on a signal obtained by fading-correcting the despread signal, and a plurality of signal power calculation circuits; A signal power average value calculating circuit for calculating an average value, and for each of the plurality of channels,
The power of the noise interference signal component is calculated for each of the plurality of channels based on the signal obtained by fading-correcting the despread signal of each of the plurality of channels and the output of the signal power average calculation circuit. A plurality of noise interference power calculation circuits, a noise interference power average value calculation circuit that calculates an average value of the outputs of the plurality of noise interference power calculation circuits, and an output of the signal power average value calculation circuit,
A signal-to-noise-interference power ratio for calculating a ratio between the power of the desired signal component and the power of the noise-interference signal component, which has been averaged with respect to the plurality of channels based on the output of the noise-interference power average value calculation circuit. It has an average value calculation circuit. By calculating the ratio between the power of the desired signal component and the power of the noise interference signal component averaged for a plurality of channels, it is possible to easily and accurately calculate the estimated value of the signal-to-noise interference power ratio. .

According to a fifth aspect of the present invention, in the signal-to-noise-interference-to-interference power ratio estimating apparatus according to the first, second, third, or fourth aspect, based on the despread signal of each of the plurality of channels. A fading distortion average value calculating circuit for calculating fading distortion for each of the plurality of channels and calculating an averaged fading distortion for the plurality of channels, and despreading each of the plurality of channels. A signal obtained by fading-correcting the output signal is output to estimate a signal-to-noise-interference power ratio. More accurate fading correction becomes possible, the power of the desired signal component and the power of the noise interference signal component averaged over a plurality of channels can be calculated more accurately, and the estimated value of the signal-to-noise interference power ratio can be easily calculated. Accuracy can be improved.

According to a sixth aspect of the present invention, in the signal-to-noise interference power ratio estimating apparatus according to the first, second, third, fourth, or fifth aspect, the despread signal of each of the plurality of channels is converted into a signal. The RAKE combining circuit outputs a signal combined by fading correction and estimates a signal-to-noise-interference power ratio. Even when there are a plurality of arriving waves, it is possible to obtain a signal obtained by synthesizing a plurality of arriving waves by performing fading correction on the despread signal of each channel, and to reduce the power of the desired signal component and the power of the noise interference signal component. Accurate calculation can be performed, and the estimated value of the signal-to-noise-interference power ratio can be easily and accurately set.

[0017]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a signal-to-noise-interference power ratio estimating apparatus according to the present invention will be described below with reference to FIGS. Here, it is assumed that the partner station inserts a pilot signal, which is a known signal, into a plurality of channels at a fixed period in slot units, and multiplexes such a plurality of channels for transmission. The slot configuration and pilot signal of the transmission signal of each channel are exactly the same, and each channel is
It is assumed that they are synchronized with each other.

FIG. 1 is a block diagram showing a first embodiment of a signal-to-noise-interference-power ratio estimating apparatus according to the present invention. In this embodiment, each of the receiving channels 103 (1) to 103 (103)
A fading distortion average value calculation circuit 109 for calculating an average value of the fading distortion of (N) is provided. Further, an in-slot signal power average value calculation circuit 110 for calculating an average value of the in-slot signal power of each of the reception channels 103 (1) to 103 (N), and each of the reception channels 103 (1) to 103 (N).
An SNIR average value calculation circuit for calculating a signal-to-noise interference power ratio averaged with respect to the channel based on the output of the intra-slot noise interference power average value calculation circuit 111 for calculating the average value of the in-slot noise interference power 113 is provided.

As in the prior art shown in FIG. 6, a transmission signal from a partner station is received by a transmission / reception antenna 101, and is converted by a high frequency circuit 102 into a base band signal in a spread band. However, different from FIG. 6, the reception channels 103 (1) to 103 (1) to 1 provided according to the number N of multiplexed channels transmitted are provided.
03 (N) is input. Each receiving channel 103 (1)
, (N), a despreading circuit 104, a fading distortion calculating circuit 108, a RAKE combining circuit 105,
An in-slot signal power calculation circuit 106 and an in-slot noise interference power calculation circuit 107 are provided.

The despreading circuit 104 performs spread demodulation by multiplying by a spread code signal assigned to each multiplexed channel, and outputs a data-modulated signal. The fading distortion calculation circuit 108 calculates the fading distortion of each of the reception channels 103 (1) to 103 (N) by using a pilot signal which is a known signal inserted in slot units of a fixed period. The fading distortion average value calculation circuit 109 is, for example, the respective channels 103 (1) to 103 (103).
By adding the fading distortion of (N) and dividing by the number N of multiplexed channels, an average value for the channels is calculated. RA of each reception channel 103 (1) to 103 (N)
The KE combining circuit 105 controls the reception channels 103 (1) to 103 (1).
The 103 (N) spread-demodulated signal is combined using the average value of the fading distortion.

[0021] Multiple channels of one user pass through the same multipath propagation path. Therefore, even in the case of a multiplex channel, fading correction should be possible by calculating the fading distortion for only one reception channel, as in the related art. However, as described as a problem of the prior art, it is possible to calculate fading distortion only in a section in which a known signal such as a pilot signal is transmitted. Have difficulty.

Therefore, the fading distortion is calculated by the fading distortion calculating circuit 108 of each of the receiving channels 103 (1) to 103 (N), and the average value of the multiplexed channel is calculated by the fading distortion average value calculating circuit 109. Has been doubled by the number of channels, so that the average value of the fading distortion becomes a more accurate estimation value, and R
In the AKE synthesis circuit 105, more accurate fading correction and synthesis can be performed.

Each of the receiving channels 103 (1) to 103 (103)
The (N) intra-slot signal power calculation circuit 106 calculates the RAK
The in-slot signal power of each of the receiving channels 103 (1) to 103 (N) is estimated based on the RAKE combining signal output from the E combining circuit 105.
An average value obtained by adding the estimated values of (1) to 103 (N) and dividing by the number N of multiplexed channels is calculated by the intra-slot signal power average value calculation circuit 110. Each receiving channel 103
(1) -103 (N) In-slot noise interference power calculation circuit 107 calculates the variance of the signal in the slot from the RAKE combined signal and the average value of the signal power in the slot, thereby obtaining the noise interference power in the slot. Is estimated. A channel average value obtained by adding the estimated values of the in-slot noise interference power of each of the reception channels 103 (1) to 103 (N) and dividing by the number of multiplexed channels N is calculated by the in-slot noise interference power average value calculation circuit 111. .

The average noise-interference-power-in-slot value is further calculated by a long-term average noise-interference-power-average value for a plurality of slots in an inter-slot average noise-interference-power calculation circuit 112. The SNIR average value calculation circuit 113
By calculating the ratio of the average value of the in-slot signal power and the average value of the inter-slot average noise interference power calculated in this way, the signal-to-noise interference power ratio averaged for the channel is calculated. Estimate the noise to interference power ratio.

As described above, multiple channels of one user pass through the same multipath propagation path. Therefore, even in the case of multiple channels, it is possible to estimate the signal-to-noise-interference power ratio of the entire received signal only by estimating the signal-to-noise-interference power ratio for only one channel. However, as in the case of fading distortion, the interval in which the in-slot noise interference power can be calculated is limited to the interval in which a known signal such as a pilot signal is transmitted. Therefore, it is not possible to accurately estimate the signal-to-noise interference power ratio. Have difficulty.

If the power of the noise interference signal component is calculated individually for each of the reception channels 103 (1) to 103 (N), the number of symbols to be calculated is substantially doubled by the number of channels. Become. as a result,
By averaging the calculated values of the power of the noise interference signal components of each of the reception channels 103 (1) to 103 (N),
An accurate value close to the statistical distribution of the power of the noise interference signal component is calculated, and the signal-to-noise interference power ratio is also averaged for multiple channels, so that accurate estimation can be performed.

On the other hand, the power of a desired signal component can be calculated without being limited to a known data symbol section such as a pilot signal. However, in the in-slot signal power calculation circuit 106, each of the reception channels 103 (1) to 103 (1) to 103
By calculating the power of the desired signal component for each (N), the number of symbols to be calculated substantially doubles by the number of channels. Therefore, if the averaging process is performed on the power of the desired signal component in the in-slot signal power average value calculation circuit 110, the estimation accuracy of the power of the desired signal component can be improved, and the signal-to-noise interference power ratio can be improved. Is also averaged with respect to multiple channels, and accurate estimation can be performed.

The number N of multiplex channels for multiplex transmission of one user
Is changed, and also when the modulation multi-level numbers of the spread modulation and data modulation are individually changed for each of the multiplex channels, the reception channels 103 (1) to 103 (1) to
3 (N) is adapted to the multi-channel transmission by calculating the signal-to-noise-interference power ratio using the average value calculated by the respective average value calculation circuits. It is possible to easily and accurately estimate the signal-to-noise-interference power ratio.

In the above description, a case has been described in which the averaging process is performed on all the reception channels of the number N of multiplex channels. However, it is not necessary to perform averaging for all channels of the multiplex channel, and averaging for two or more channels provides higher accuracy than when calculating only one channel. In the illustrated example, the inter-slot average noise interference power calculation circuit 112 is provided. However, if the number of symbols for which the noise interference power is substantially calculated is sufficient, the intra-slot noise interference power average value calculation circuit 112 is provided. The output of 111 may be directly output to the SNIR average value calculation circuit 113.

FIG. 2 is a block diagram showing a second embodiment of the signal-to-noise-interference power ratio estimation apparatus of the present invention. In this embodiment, each of the receiving channels 203 (1) to 203 (1) to 203
An SNIR average value calculation circuit 213 for calculating a signal-to-noise-interference power ratio based on the output of the SNIR calculation circuit 214 for calculating the signal-to-noise-interference power ratio of (N) is provided.

The transmission signal from the partner station is transmitted and received by the transmitting / receiving antenna 2
01, is converted into a base band signal of a spread band by a high frequency circuit 202, and is received by reception channels 203 (1) to 203 (2).
03 (N) is input. Each receiving channel 203 (1)
.. 203 (N), a despreading circuit 204, a fading distortion calculating circuit 208, a RAKE combining circuit 205, an in-slot signal power calculating circuit 206, and an in-slot noise interference power calculating circuit 207 are provided. A power calculation circuit 212 and an SNIR calculation circuit 214 are provided. Here, each reception channel 203 (1)
Since the in-slot noise interference power calculation circuit 207 and the in-slot signal power calculation circuit 206 are provided for each of N to 203 (N), the in-slot noise interference power, the in-slot signal power, It has substantially doubled by the number of channels.

The SNIR calculation circuit 214 calculates a signal-to-noise-interference power ratio for each of the reception channels 203 (1) to 203 (N). These are sent to the SNIR average value calculation circuit 213.
, And dividing by the number N of multiplexed channels to calculate a signal-to-noise-interference power ratio averaged for the channels. The SNIR average value calculation circuit 213 substantially
Since the signal-to-noise-interference power ratio is calculated for a larger number of symbols than in the past, it is possible to estimate with high accuracy.

FIG. 3 is a block diagram showing a third embodiment of the signal-to-noise-interference-power ratio estimating apparatus according to the present invention. This embodiment differs from the configuration of the second embodiment described with reference to FIG. 2 in that the fading distortion average value calculation circuit 1 shown in FIG.
In this embodiment, a fading distortion average value calculation circuit 309 similar to that shown in FIG. A transmission signal from the partner station is received by a transmission / reception antenna 301, converted into a baseband signal in a spread band by a high frequency circuit 302, and input to first to Nth reception channels 303 (1) to 303 (N). . A despreading circuit 3 is provided for each of the reception channels 303 (1) to 303 (N).
04, a fading distortion calculation circuit 308, a RAKE combining circuit 305, an in-slot signal power calculation circuit 306, an in-slot noise interference power calculation circuit 307, an inter-slot average noise interference power calculation circuit 312, and an SNIR calculation circuit 314.

Each of the receiving channels 303 (1) to 303
With respect to the fading distortion of (N), the average value of the channel is calculated by a fading distortion average value calculating circuit 309, and R
Output to the AKE synthesis circuit 305. RA of spread demodulated signal
After the KE combining, each of the receiving channels 303 (1) to 303 (1) to 303
The signal-to-noise-interference power ratio is calculated for each (N), the average value for the channel is calculated by the SNIR average value calculation circuit 313, and the signal-to-noise-interference power ratio is estimated. Therefore, good fading correction and combining can be performed, and the signal-to-noise-interference power ratio can be accurately estimated.

FIG. 4 is a block diagram showing a fourth embodiment of the signal-to-noise-interference power ratio estimating apparatus according to the present invention. This embodiment differs from the configuration of the second embodiment described with reference to FIG. 2 in that the intra-slot signal power average value calculation circuit 4 similar to the intra-slot signal power average value calculation circuit 110 of FIG.
10 is provided.

The transmission signal from the partner station is transmitted and received by the transmitting / receiving antenna 4
01, is converted to a base band signal of a spread band by a high frequency circuit 402, and is received by reception channels 403 (1) to 403 (4).
03 (N) is input. Each receiving channel 403 (1)
403 (N), a despreading circuit 404, a fading distortion calculating circuit 408, a RAKE combining circuit 405, an in-slot signal power calculating circuit 406, an in-slot noise interference power calculating circuit 407, and an inter-slot average noise interference power calculating circuit 4
12, an SNIR calculation circuit 414 is provided.

Each of the receiving channels 403 (1) to 403
In the (N) in-slot signal power calculation circuit 406, RAK
The in-slot signal power of each of the reception channels 403 (1) to 403 (N) is estimated from the combined signal output from the E combining circuit 405, and the average value for the channels is calculated by the in-slot signal power average value calculation circuit 410. . Thereafter, the signal-to-noise-interference power ratio is calculated for each of the reception channels 403 (1) to 403 (N), and the average value of the signal-to-noise-interference power ratio for the channels is calculated by the SNIR average value calculation circuit 413. Thus, the signal-to-noise-interference power ratio, which has been averaged with respect to the channel, is calculated, and the signal-to-noise-interference power ratio is estimated. In the in-slot signal power average value calculation circuit 410, each of the reception channels 403 (1) to 403
Since the in-slot signal power of (N) is averaged, a more accurate signal-to-noise-interference power ratio can be calculated as compared with the second embodiment described with reference to FIG.

FIG. 5 is a block diagram showing a fifth embodiment of the signal-to-noise-interference-power ratio estimating apparatus according to the present invention. This embodiment differs from the configuration of the second embodiment described with reference to FIG. 2 in that the intra-slot noise interference power average value calculation circuit 511 similar to the intra-slot noise interference power average value calculation circuit 111 in FIG. It is provided with.

The transmission signal from the partner station is transmitted and received by the transmitting / receiving antenna 5
01, is converted into a base band signal of a spread band by a high frequency circuit 502, and is received by reception channels 503 (1) to 503 (5).
03 (N) is input. Receive channel 503 (1)-
For each 503 (N), a despreading circuit 504, a fading distortion calculation circuit 508, a RAKE combining circuit 505, an in-slot signal power calculation circuit 506, an in-slot noise interference power calculation circuit 507, and an SNIR calculation circuit 514 are provided.

Each of the receiving channels 503 (1) to 503
(N) In-slot signal power calculation circuit 506 calculates the in-slot noise interference power, calculates the average value for the channel in the in-slot noise interference power average value calculation circuit 511, and calculates the average noise interference between slots. Power calculation circuit 51
In 2, the long-term average noise interference power for a plurality of slots is calculated. Thereafter, each reception channel 503
The signal-to-noise-interference power ratio is calculated for each of (1) to 503 (N), and the average value for the channel is calculated by the SNIR average value calculation circuit 513 to estimate the signal-to-noise-interference power ratio. In the noise interference power average calculation circuit 511 in the slot,
Since the intra-slot noise interference power of each of the reception channels 503 (1) to 503 (N) is averaged, the signal-to-noise interference power is more accurate than in the second embodiment described with reference to FIG. The ratio can be calculated.

The third to fifth embodiments shown in FIGS. 3 to 5 are different from the first embodiment having the SNIR average value calculation circuit 213 shown in FIG. The average value calculation circuit 309, the in-slot signal power average value calculation circuit 410, and the in-slot noise interference power average value calculation circuit 511 are individually added. Also,
The configuration obtained by adding all three circuits is the first configuration shown in FIG.
It is an embodiment of the present invention. Although not shown, a configuration in which any two of these three circuits are added to the configuration shown in FIG. 2 is another embodiment of the present invention. Figure 2 above
Some circuit blocks for calculating the average value have been deleted from the configuration of the first embodiment shown in FIG. 1, including the block configuration examples of the second to fifth embodiments shown in FIG. This has the advantage that it can be realized with a configuration in which the amount of circuits is reduced.
However, since the number of circuit blocks for the average value calculation processing is reduced, the estimation accuracy of the signal-to-noise-interference power ratio is slightly deteriorated as compared with the first embodiment shown in FIG.

In the above description, in each of the embodiments, the despread signals of a plurality of arriving waves are combined using the RAKE combining circuit. However, it is also possible to estimate the signal-to-noise-interference power ratio for one of the arriving waves without performing signal combining of a plurality of arriving waves by RAKE combining. In this case, the RAKE combining circuit is replaced with a fading phase correction circuit that corrects only the fading phase using the output of the fading distortion calculation circuit, and outputs a phase-corrected signal. Here, the fading distortion is a combination of the level fluctuation and the phase fluctuation, but the fading correction may be performed by correcting only the phase or only the level fluctuation.

On the other hand, the power of the desired signal component can be calculated by calculating the power fluctuation due to the fading envelope fluctuation, so that the power of the above-mentioned fading phase corrected signal or the despread signal not subjected to the fading phase correction is obtained. Then, the power of the desired signal component is calculated by the in-slot signal power calculation circuit, and the noise interference component is calculated by the in-slot noise interference power calculation circuit.

[0044]

As described above, the signal-to-noise-interference power ratio estimating apparatus of the present invention has an effect that the signal-to-noise-interference power ratio can be easily and accurately estimated. In particular, in a multimedia communication system in which one user multiplexes a plurality of channels and further changes the number of multiplexed channels, signal-to-noise corresponding to fluctuations in inter-user interference due to increase or decrease in traffic. The interference power ratio can be easily and accurately estimated.
Therefore, the transmission power control, the number of multiplexed channels, and the change in the number of modulation levels for each multiplexed channel can be optimized, and more efficient transmission can be performed without deteriorating the transmission data error rate. Becomes possible.

[Brief description of the drawings]

FIG. 1 shows a first example of a signal-to-noise-interference-power ratio estimation apparatus according to the present invention.
It is a block diagram showing an embodiment.

FIG. 2 shows a second example of the signal-to-noise-interference-power ratio estimation apparatus of the present invention.
It is a block diagram showing an embodiment.

FIG. 3 shows a third example of the signal-to-noise-interference-power ratio estimation apparatus of the present invention.
It is a block diagram showing an embodiment.

FIG. 4 shows a fourth example of the signal-to-noise-interference power ratio estimation apparatus of the present invention.
It is a block diagram showing an embodiment.

FIG. 5 shows a fifth example of the signal-to-noise-interference-power ratio estimation apparatus of the present invention.
It is a block diagram showing an embodiment.

FIG. 6 is a block diagram showing a conventional signal to noise interference power ratio estimating apparatus.

[Explanation of symbols]

101, 201, 301, 401, 501, 601 transmit / receive antennas 102, 202, 302, 402, 502, 602 high frequency circuits 103, 203, 303, 403, 503, 603 receive channels 104, 204, 304, 404, 504, 604 Despreading circuit 105, 205, 305, 405, 505, 605 RAKE combining circuit 106, 206, 306, 406, 506, 606 In-slot signal power calculation circuit 107, 207, 307, 407, 507, 607 In-slot noise interference power Calculation circuits 108, 208, 308, 408, 508, 608 Fading distortion calculation circuits 109, 309 Fading distortion average calculation circuits 110, 410 Average signal power in slot calculation circuit 111, 511 Average noise interference power in slots Value calculation circuit 112, 212, 312, 412, 512, 612 Average inter-slot noise interference power calculation circuit 113, 213, 313, 413, 513 SNIR average value calculation circuit 214, 314, 414, 514, 614 SNIR calculation circuit

Continuation of the front page (58) Field surveyed (Int.Cl. ⁷ , DB name) H04J 13/04 H04B 7/26

Claims (6)

(57) [Claims] 1. A spread modulation signal, which is obtained by multiplexing a channel including a known signal at a predetermined period interval and transmitted from a partner station, is received, and the power of a desired signal component and the power of a noise interference signal component are compared. A signal-to-noise-interference power ratio estimating apparatus for estimating a ratio, wherein, for a plurality of channels among multiplexed channels to be received, a power of the desired signal component calculated for each of the plurality of channels; Calculating a ratio between the power of the desired signal component and the power of the noise interference signal component, which has been averaged with respect to the plurality of channels, based on the power of the noise interference signal component calculated for each channel. And estimating a ratio of the power of the desired signal component to the power of the noise interference signal component. 2. For each of the plurality of channels,
Calculating a power of the desired signal component for each of the plurality of channels based on a despread signal of each of the plurality of channels or a signal obtained by fading-correcting the despread signal; A circuit, a signal power average value calculation circuit that calculates an average value of outputs of the plurality of signal power calculation circuits, and a signal obtained by fading-correcting a despread signal of each of the plurality of channels, for the plurality of channels, A plurality of noise interference power calculation circuits for calculating the power of the noise interference signal component for each of the plurality of channels based on an output of the signal power average value calculation circuit; and the signal power average value calculation circuit. , And, based on the outputs of the plurality of noise interference power calculation circuits, were averaged for the plurality of channels. The signal-to-noise-interference power ratio according to claim 1, further comprising a signal-to-noise-interference power ratio average value calculation circuit that calculates a ratio between the power of the desired signal component and the power of the noise-interference signal component. Estimation device. 3. The method according to claim 2, wherein:
Calculating a power of the desired signal component for each of the plurality of channels based on a despread signal of each of the plurality of channels or a signal obtained by fading-correcting the despread signal; A circuit, for each of the plurality of channels, based on a signal obtained by fading-correcting the despread signal of each of the plurality of channels, and an output of the plurality of signal power calculation circuits, for each of the plurality of channels. A plurality of noise interference power calculation circuits for calculating the power of the noise interference signal component; a noise interference power average value calculation circuit for calculating an average value of outputs of the plurality of noise interference power calculation circuits; and the plurality of signal powers A calculation circuit, and an averaging process for the plurality of channels based on an output of the noise interference power average value calculation circuit. 2. The signal-to-noise interference power according to claim 1, further comprising a signal-to-noise-interference power ratio average value calculation circuit that calculates a ratio between the power of the desired signal component and the power of the noise interference signal component. Ratio estimator. 4. The plurality of channels,
Calculating a power of the desired signal component for each of the plurality of channels based on a despread signal of each of the plurality of channels or a signal obtained by fading-correcting the despread signal; A circuit, a signal power average value calculation circuit that calculates an average value of outputs of the plurality of signal power calculation circuits, and a signal obtained by fading-correcting a despread signal of each of the plurality of channels, for the plurality of channels, And a plurality of noise interference power calculation circuits, each calculating the power of the noise interference signal component for each of the plurality of channels, based on an output of the signal power average value calculation circuit, and the plurality of noise interference power calculations A noise interference power average value calculation circuit for calculating an average value of the output of the circuit, and an output of the signal power average value calculation circuit; and A signal-to-noise-interference power ratio average for calculating a ratio between the power of the desired signal component and the power of the noise-interference signal component averaged with respect to the plurality of channels based on the output of the noise-interference power average calculation circuit. The signal-to-noise-interference-power ratio estimating device according to claim 1, further comprising a value calculating circuit. 5. A fading distortion is calculated for each of the plurality of channels based on a despread signal of each of the plurality of channels, and a fading distortion averaged for the plurality of channels is calculated. A fading distortion average value calculating circuit that outputs a signal obtained by fading-correcting the despread signal of each of the plurality of channels, and estimates a signal-to-noise interference power ratio. , 3 and 4, the signal-to-noise interference power ratio estimating apparatus. 6. A signal obtained by subjecting a despread signal of each of the plurality of channels to a fading correction by a RAKE combining circuit and outputting the combined signal to estimate a signal-to-noise-interference power ratio. 1,2,3,4,5
3. The signal-to-noise-interference power ratio estimating apparatus according to item 1.