JP4744461B2 - Reception control method and receiving apparatus - Google Patents

Description

  The present invention relates to a reception control method for digitally converting and demodulating an analog signal received by an antenna in a mobile station or a communication apparatus, and a receiving apparatus for digitally converting and demodulating the analog signal received by the antenna. .

As a conventional example of a receiving apparatus that digitally converts and demodulates an analog signal received by an antenna, there are those shown in FIGS. 5 and 6, for example.
The conventional receiving apparatus shown in FIG. 5 is configured as a direct conversion type receiving apparatus, and an input signal from an antenna 100 passes through a band-pass filter 101 and an amplifier 102 and is transmitted from a local signal source 104. By the emitted signal, the quadrature demodulator 103 down-converts it into Ich and qch baseband signals. Each signal passes through the low-pass filter 105 and the variable amplifier 106, converted into a digital signal by the A / D converter 107, and then demodulated by the reception baseband unit (RXBB) 112. The RXBB 112 measures the reception level, sends gain data from the CONT unit 113 to the variable amplifier 106, and the gain is set by an automatic gain control circuit including the variable amplifier 106 based on this gain data.
The conventional receiving apparatus shown in FIG. 6 is configured as a superheterodyne receiving apparatus, and an input signal from the antenna 100 passes through a bandpass filter 101 and an amplifier 102, and a local signal source 104 and a mixer 113. Is converted into a primary IF signal. After that, after passing through the low-pass filter 105 and amplified to an appropriate level by the variable amplifier 106, it is converted again to a secondary IF signal by the mixer 108. The secondary IF signal passes through the band-pass filter 110 and is digitally converted by the A / D converter 111. The RXBB unit 112 performs demodulation after converting the input signal into a baseband signal. In accordance with the RSSI level detected by the RXBB unit 112, the CONT unit 113 sends gain data to the variable amplifier 106, and the gain is set by an automatic gain control circuit including the variable amplifier 106 based on the gain data.
As a conventional example of an automatic gain control circuit, there is an automatic gain control circuit that sets the gain of a variable amplifier by feedback control based on a detected fading pitch (see, for example, Patent Document 1).

  In the mobile station including the TDMA and TDD receivers, in the conventional example shown in FIGS. 5 and 6, the analog signal received by the antenna is amplified by the reception amplifier, and the amplified reception signal is A / D. After digital conversion by the converter, the baseband processing unit measures a received signal strength indicator (RSSI) of the digitally converted received signal. Then, based on the measured received electric field strength, a feedback process for setting the gain of the receiving amplifier for amplifying the next received signal is performed. Such a gain setting of the reception amplifier is performed in a slot next to the reception slot in which the reception electric field strength is measured.

JP 2001-230644 A

However, when the mobile station moves at a high speed, the received electric field strength fluctuates until the next slot of the reception slot whose received electric field strength is measured by the receiving device of the mobile station. Even if the gain of the receiving amplifier is set based on the above, the frequency of deviating from the dynamic range of the A / D converter becomes extremely high. Moreover, since the same gain (gain) is set in the slot, it is difficult to cope with the level fluctuation in the slot. For this reason, when the reception level fluctuates between reception slots or within the reception slot, the contents cannot be reflected in the feedback loop, so the reception level fluctuation cycle is accelerated and there is a fluctuation within the slot. In this case, appropriate signal conversion processing from an analog signal to a digital signal cannot be performed, and reception performance may be deteriorated.
Therefore, in order to avoid the above-described problem, it is conceivable to speed up a series of processing from measurement of the received electric field strength of the digitized received signal to setting of the gain of the receiving amplifier. However, since the amount of calculation increases, the processing load of the receiving apparatus increases.

A first object of the present invention is to provide a reception control method capable of appropriately setting a gain of a reception amplifier in accordance with the movement status of a mobile station (receiving apparatus) and the modulation scheme (modulation class) of the mobile station. And
It is a second object of the present invention to provide a receiving apparatus capable of appropriately setting a gain of a receiving amplifier in accordance with a moving state of a mobile station (receiving apparatus) and a modulation scheme (modulation class) of the mobile station. To do.

  In order to achieve the first object, a reception control method according to claim 1 is a reception control method in which a mobile station digitally converts an analog signal received by an antenna and demodulates the analog signal. A first step of grasping a speed, and when the grasped moving speed is equal to or greater than a predetermined threshold, the gain of a receiving amplifier is controlled based on a received electric field strength of an analog signal received by the antenna, and the moving A second step of digitally converting the analog signal and controlling a gain of the reception amplifier based on a received electric field strength of the digitally converted received signal when the speed is less than the predetermined threshold value; It is characterized by that.

  To achieve the first object, a reception control method according to claim 2 is a reception control method for digitally converting and demodulating an analog signal received by an antenna in a communication apparatus that performs communication using an adaptive modulation scheme. In the first step of grasping the modulation method of the communication apparatus, and when the grasped modulation method is a modulation method that is less than a predetermined multi-value number, reception of an analog signal received by the antenna The gain of the reception amplifier is controlled based on the electric field strength, and when the modulation method is a modulation method exceeding the predetermined multi-value number, the analog signal is digitally converted to receive the digitally converted reception signal. And a second step of controlling the gain of the receiving amplifier based on the electric field strength.

  In order to achieve the first object, a reception control method according to claim 3 is a reception control method in which an analog signal received by an antenna is digitally converted and demodulated in a mobile station that performs communication using an adaptive modulation scheme. The first step of grasping the moving speed and modulation scheme of the mobile station, the grasped moving speed is equal to or higher than a predetermined threshold, and the modulation scheme of the mobile station is less than a predetermined multi-value number. In the case of a modulation scheme, the gain of the reception amplifier is controlled based on the received electric field strength of the analog signal received by the antenna, the moving speed is less than the predetermined threshold, and the modulation scheme of the mobile station Is a modulation scheme exceeding the predetermined multi-level number, the analog signal is digitally converted and the reception amplifier gain is based on the received electric field strength of the digitally converted received signal. Characterized in that it comprises a second step of controlling the emissions, the.

  In order to achieve the second object, a receiving apparatus according to claim 4 is a receiving apparatus in a mobile station, which digitally converts an analog signal received by an antenna and demodulates the analog signal. First receiving amplifier control means for controlling the gain of the receiving amplifier based on the received electric field strength; and the analog signal received by the antenna is digitally converted and the received electric signal strength of the digitally converted received signal is A second reception amplifier control means for controlling the gain of the reception amplifier; a movement speed acquisition means for acquiring information on the movement speed of the mobile station; and the movement speed is set to a predetermined threshold based on the acquired information on the movement speed. If it is above, the gain of the receiving amplifier is controlled by the first receiving amplifier control means, and the moving speed is If it is less than the constant threshold value, it controls the gain of the receiving amplifier by the second receiving amplifier control means, characterized in that it comprises a receiving amplifier control switching means.

  In order to achieve the second object, a receiving apparatus according to claim 5 performs communication using an adaptive modulation scheme, digitally converts an analog signal received by an antenna, and demodulates the analog signal. First reception amplifier control means for controlling the gain of the reception amplifier based on the received electric field strength of the received analog signal; and receiving the digitally converted reception signal by digitally converting the analog signal received by the antenna Second reception amplifier control means for controlling the gain of the reception amplifier based on electric field strength; modulation method acquisition means for acquiring information on the modulation method of the mobile station; and the acquired modulation method is a predetermined multi-value number. If the modulation scheme is less than 1, the gain of the reception amplifier is controlled by the first reception amplifier control means. When the modulation scheme exceed the number of multi-level controls the gain of the receiving amplifier by the second receiving amplifier control means, characterized in that it comprises a receiving amplifier control switching means.

  In order to achieve the second object, a receiving apparatus according to claim 6 performs communication using an adaptive modulation scheme, and performs digital conversion on an analog signal received by an antenna and demodulates the analog signal. A first receiving amplifier control means for controlling a gain of a receiving amplifier based on a received electric field strength of the analog signal received by the antenna; and the analog signal received by the antenna is digitally converted and digitally converted. A second receiving amplifier control means for controlling a gain of the receiving amplifier based on a received electric field strength of a received signal; a moving speed acquiring means for acquiring information relating to a moving speed of the mobile station; and a modulation scheme of the mobile station Modulation method acquisition means for acquiring information, the acquired moving speed is a predetermined threshold value or more, and the acquired modulation method is a predetermined multi-value If the modulation scheme is less than 1, the gain of the reception amplifier is controlled by the first reception amplifier control means, the acquired moving speed is less than the predetermined threshold, and the acquired modulation scheme is In the case of a modulation scheme exceeding the predetermined multi-valued number, a reception amplifier control switching means for controlling the gain of the reception amplifier by the second reception amplifier control means is provided.

  The first reception amplifier control means includes a loop filter, and when the moving speed acquired by the moving speed acquisition means is equal to or greater than a predetermined threshold, the time constant of the loop filter is relatively small. When the moving speed is less than a predetermined threshold value, the time constant of the loop filter is controlled so as to be relatively large, the movement status of the mobile station (receiving device) It is preferable to provide a receiving apparatus capable of appropriately controlling the time constant of a feedback loop (loop filter) for setting a gain of a receiving amplifier in accordance with the modulation scheme (modulation class) of the mobile station.

  The first reception amplifier control means includes a loop filter, and when the modulation method acquired by the modulation method acquisition means is a modulation method that does not satisfy a predetermined multi-value number, The constant is controlled to be relatively small, and when the modulation method is a modulation method exceeding a predetermined multi-value number, the time constant of the loop filter may be controlled to be relatively large. Reception that can appropriately control the time constant of the feedback loop (loop filter) for gain setting of the receiving amplifier according to the movement status of the mobile station (receiving device) and the modulation method (modulation class) of the mobile station Preferred for providing the device.

  According to the present invention, the gain of the reception amplifier is controlled based on the received electric field strength of the analog signal, or the digitally converted received signal is converted in accordance with the movement status of the mobile station and the modulation method (modulation class) of the mobile station. Since the gain of the receiving amplifier is controlled based on the received electric field strength, the receiving control method and the receiving apparatus that can appropriately set the gain of the receiving amplifier according to the movement status of the mobile station and the modulation method of the mobile station Can be provided.

Hereinafter, the best mode for carrying out the present invention will be described in detail with reference to the drawings.
FIG. 1 is a circuit diagram illustrating the configuration of the receiving apparatus according to the first embodiment of this invention. The receiving apparatus according to the present embodiment is configured to switch signals used for gain control of the receiving amplifier according to the moving speed of the receiving apparatus. As shown in FIG. 1, the antenna 10 and the bandpass filter 11 are switched. , Amplifier 12, quadrature demodulator 13, local oscillation signal source 14, band pass filter 15, reception amplifier (variable amplifier) 16, quadrature demodulator 18, local oscillation signal source 19, band pass filter 20, A / D converter 21, A reception baseband unit (RXBB) 22, a CONT unit 23, a log amplifier (LogAMP) 24, a loop filter (variable low-pass filter) 25, a switch (SW) 26, and a D / A converter 27 are provided.

This receiving apparatus is configured to switch the data corresponding to the amplifier gain setting data from the CONT unit 113 in the conventional receiving apparatus shown in FIG. 6 and the feedback signal from the reception level detected by the LOG amplifier 24 with the switch 26. As a switching signal of the switch 26, when the speed exceeds a predetermined threshold by the CONT unit 23 to which speed information is input from the outside (in the case of high speed), the loop switching is performed from the CONT unit 23. A signal is sent to the switch 26 so that the signal from the feedback loop of the LOG amplifier 24 is selected. The loop filter 25 in the feedback loop of the LOG amplifier 24 can variably control the time constant by an external signal because the CONT unit 23 sends a time constant control signal according to the speed information.
That is, in this receiving apparatus, the input signal from the antenna 10 passes through the band-pass filter 11 and the amplifier 12 and is down-converted to an IF signal by the orthogonal demodulator 13 by the local signal from the local signal source 14. Thereafter, the signal passes through the band pass filter 15 and is amplified to an appropriate level by the reception amplifier 16, and then passes through the reception amplifier 16, the quadrature demodulator 18 and the band pass filter 20, and is digitally converted by the A / D converter 21 After being converted into a signal, the reception baseband unit (RXBB) 22 performs demodulation processing. Then, the RXBB 22 measures the reception level, and the time constant control signal is input to the loop filter 25 from the CONT unit 23 to which the speed information is input from the outside, and the speed signal is input to the switch 26 via the D / A converter 27. By inputting the loop switching signal to the switch 26, the gain is set in the receiving amplifier 16 in accordance with the signal selectively input to the receiving amplifier 16.
In the receiving apparatus shown in FIG. 1, the time constant is controlled in two stages, but the number of stages can be increased in accordance with the modulation method and speed.

  FIG. 2 is a diagram illustrating various signals used in the receiving apparatus according to the first embodiment. FIG. 2 shows the received signal of the Nth frame composed of “(N Flame) received data”, and the (N + 1) th frame composed of “guard bit training symbol” and “(N + 1 Flame) received data”. As shown in the figure, the waveform of the variable low-pass filter 25 changes from the end of the received signal of the Nth frame to the end of the “guard bit training symbol” of the received signal of the (N + 1) th frame. If the predetermined target level is exceeded until the loop switching signal is active before the reception signal of the (N + 1) th frame is received as shown in the figure, the time constant control signal is shown in the figure. Shows an example of active switching from the start to the end of the “guard bit training symbol”.

  Next, switching conditions and time constant control conditions of the switch 26 in the receiving apparatus will be described.

[Switching condition 1 of the switch 26; using only the moving speed of the receiving device]
When the receiving apparatus is a receiving apparatus in a mobile station, when the analog signal received by the antenna 10 is digitally converted and demodulated and output as received data, (1) the moving speed of the receiving apparatus (mobile station) Is equal to or higher than a predetermined threshold (high speed), the switch 26 inputs a loop switching signal for selecting “the feedback loop of the LOG amplifier 24” to the switch 26, whereby the analog signal received by the antenna 10 is received. (2) When the moving speed is less than the predetermined threshold value (low speed), the switch 26 sets the “D / A converter feedback loop”. By inputting a loop switching signal to be selected to the switch 26, the received electric field of the received signal obtained by digitally converting the analog signal is obtained. So as to control the gain of the receiving amplifier based on time.

[Switching condition 2 of the switch 26; using only the modulation class of the modulation method of the receiving apparatus]
When the receiving apparatus is a receiving apparatus in a mobile station, when the analog signal received by the antenna 10 is digitally converted and demodulated and output as received data, (1) the modulation method of the receiving apparatus (mobile station) When the modulation scheme (modulation class) is less than a predetermined multi-value number (low modulation class), a switch signal is input to the switch 26 so that the switch 26 selects “feedback loop of the LOG amplifier 24”. Thus, the gain of the reception amplifier 16 is controlled based on the received electric field strength of the analog signal received by the antenna 10, and (2) the modulation method (modulation class) exceeds the predetermined multi-value number ( In the case of the high modulation class), a switch signal is selected so that the switch 26 selects “D / A converter feedback loop”. By entering, so as to control the gain of the receiving amplifier based on the analog signal to the reception field strength of the received signal digitally converted. Note that examples of modulation schemes that do not satisfy the predetermined multilevel number include, for example, BPSK and BPSK +, and examples of modulation schemes that exceed the predetermined multilevel number include, for example, 10QAM and 24QAM. (The same applies hereinafter).

[Switching condition 3 of the switch 26; when using the moving speed and modulation method of the receiving apparatus]
When the receiving apparatus is a receiving apparatus in a mobile station, when the analog signal received by the antenna 10 is digitally converted and demodulated and output as received data, (1) the movement of the receiving apparatus (mobile station) When the speed is equal to or higher than a predetermined threshold (high speed) and the modulation scheme (modulation class) of the receiving device (mobile station) is a modulation scheme (low modulation class) that does not satisfy the predetermined multi-value number, By inputting a loop switching signal such that the switch 26 selects “feedback loop of the LOG amplifier 24” to the switch 26, the gain of the reception amplifier 16 is controlled based on the received electric field strength of the analog signal received by the antenna 10. (2) The moving speed of the receiving apparatus (mobile station) is less than a predetermined threshold (low speed), and the modulation method (modulation class) of the receiving apparatus (mobile station) is When the modulation method exceeds the number of values (high modulation class), the switch 26 inputs a loop switching signal that selects the “D / A converter feedback loop” to the switch 26, so that the analog signal is The gain of the receiving amplifier is controlled based on the received electric field strength of the digitally received signal.

[Time constant control condition 1: When only the moving speed of the receiving device is used]
When the moving speed of the receiving apparatus (mobile station) is equal to or higher than a predetermined threshold (high speed), the time constant of the loop filter 25 is controlled so as to shorten the time (the time constant of the loop filter 25 becomes relatively small). When the moving speed is less than the predetermined threshold value (low speed), the time constant of the loop filter 25 is controlled so that the time becomes longer (the time constant of the loop filter 25 is relatively large). To be controlled).

[Time constant control condition 2: When using only the modulation method of the receiving apparatus]
When the modulation method (modulation class) of the receiving apparatus (mobile station) is a modulation method (high modulation class) exceeding a predetermined multi-value number, the time constant of the loop filter 25 is controlled so that the time becomes longer (loop) When the time constant of the filter 25 is controlled to be relatively large), and the modulation method (modulation class) of the receiving device (mobile station) is a modulation method (low modulation class) that does not satisfy the predetermined multi-value number First, the time constant of the loop filter 25 is controlled so that the time is shortened (the time constant of the loop filter 25 is controlled to be relatively small).
As a modulation method of the receiving apparatus, BPSK corresponding to modulation method 0, BPSK + corresponding to modulation method 1, QPSK corresponding to modulation method 2, QPSK + corresponding to modulation method 3, 8PSK corresponding to modulation method 4, There are 8PSK + corresponding to the modulation scheme 5, 12QAM corresponding to the modulation scheme 6, 16QAM corresponding to the modulation scheme 7, and 24QAM corresponding to the modulation scheme 8, and information on the modulation schemes of the modulation schemes of these receiving apparatuses is externally provided. It may be inputted or extracted from the received signal.

According to the receiving apparatus of the first embodiment and the receiving control method of the first embodiment, in the automatic gain control circuit included in the receiving apparatus in the mobile station, the receiving amplifier is based on the received electric field strength (for example, RSSI signal) of the received signal. When controlling the gain of 16, based on the moving speed of the receiving device (mobile station), a “feedback loop of the LOG amplifier 24” that can follow level fluctuations is used during high-speed movement, and “D / A” is used during low-speed movement. By switching the feedback loop to use the “converter feedback loop”, the input level of the A / D converter 21 is optimized not only during low-speed movement but also during high-speed movement. ) Can exhibit optimum performance according to the moving speed.
Further, according to the receiving apparatus of the first embodiment and the receiving control method of the first embodiment, by controlling the time constant of the “feedback loop of the LOG amplifier 24” based on the moving speed of the receiving apparatus (mobile station). It is possible to realize a stable feedback loop during low-speed movement and to follow level fluctuations during high-speed movement.
Furthermore, according to the receiving apparatus of the first embodiment and the reception control method of the first embodiment, when the adaptive modulation scheme is employed, the “feedback loop of the LOG amplifier 24” when the modulation scheme is a low modulation scheme. And when the modulation method is a high modulation method, the feedback loop is switched so that the “D / A converter feedback loop” is used, and based on the modulation method (modulation class) of the receiving apparatus (mobile station). By changing the time constant of the “feedback loop of the LOG amplifier 24” to variably control the integration time corresponding to the amplitude variation depending on the modulation method, the detection level varies depending on the modulation method when the reception level is detected with a constant integration time. Since it is possible to ensure the same detection level accuracy with the same accuracy, it is possible to eliminate the feedback loop caused by the modulation method. It is possible to reduce the qualitative.

  The reception control method of the first embodiment includes a receiving device in a mobile station, a receiving device that performs communication using an adaptive modulation scheme, a receiving device in a mobile station that performs communication using an adaptive modulation scheme, The present invention can also be applied to a communication apparatus that performs communication using an adaptive modulation scheme.

  FIG. 3 is a circuit diagram illustrating the configuration of the receiving apparatus according to the second embodiment of the invention. The receiving apparatus of the present embodiment is configured to switch signals used for gain control of the receiving amplifier in accordance with the moving speed of the receiving apparatus, and as shown in FIG. , Amplifier 12, quadrature demodulator 13, local oscillation signal source 14, band pass filter 15, reception amplifier (variable amplifier) 16, quadrature demodulator 18, local oscillation signal source 19, band pass filter 20, A / D converter 21, A reception baseband unit (RXBB) 22, a CONT unit 23, a log amplifier (LogAMP) 24, a loop filter (variable low-pass filter) 25, a switch (SW) 26, an arithmetic circuit (CAL) 28, and a selector (SEL) 29 are provided. It consists of

  The difference between the receiving apparatus of the present embodiment and the receiving apparatus of the first embodiment is that the receiving apparatus of the first embodiment is assumed to be input from the outside, “the moving speed of the receiving apparatus (mobile station) is “Speed information to be indicated” is changed to be generated (estimated) inside the receiving apparatus. Below, the detection method (estimation method) of speed information is demonstrated based on FIG.

  FIG. 4 is a diagram illustrating various signals used in the receiving apparatus according to the second embodiment. In FIG. 4, the received signal of the (N + 1) th frame composed of “training symbol (head part)”, “(N + 1 Flame) received data”, and “training symbol (tail part)” is received. In the meantime, as shown in the figure, a training symbol timing signal having a waveform that is switched only between “training symbol (head portion)” and “training symbol (tail portion)” together with the detection signal of the Log amplifier 24 is calculated by an arithmetic circuit (CAL). ) 28, the level fluctuation between the rear end of the head and the tail of the training symbol of the reception slot (the difference between the reception level at the instant t1 of the variable low-pass filter 25 and the reception level at the instant t2). Is detected from the reception level difference) and the level fluctuation is greater than or equal to a predetermined threshold In some cases (when the level fluctuation is large), it is estimated that the moving speed of the receiving device (mobile station) is high, and when the level fluctuation is less than a predetermined threshold (when the level fluctuation is small), reception is performed. The moving speed of the device (mobile station) is estimated to be low. When the moving speed of the receiving device (mobile station) is low, the switch (SW) 26 is switched so that the feedback loop for guiding the output signal of the CONT unit 23 is selected, and the receiving device (mobile station) When the moving speed is high, the switch (SW) 26 is switched so that “the feedback loop of the LOG amplifier 24” is selected, and the output signal of the arithmetic circuit (CAL) 28 and the output signal of the CONT unit 23 are switched. By supplying a time constant control signal output from the input selector (SEL) 29 to the loop filter (variable low-pass filter) 25, the time constant of the “feedback loop of the LOG amplifier 24” is variably controlled.

  The switching condition and time constant control condition of the switch 26 in the receiving apparatus of this embodiment are the same as those of the receiving apparatus of the first embodiment.

  According to the receiving apparatus of the second embodiment and the receiving control method of the second embodiment, the same effects as those of the receiving apparatus of the first embodiment and the receiving control method of the first embodiment can be obtained. In addition, according to the receiving apparatus of the second embodiment and the receiving control method of the second embodiment, there is no need to input speed information from the outside in order to switch the feedback loop, so that the circuit configuration can be simplified. can get.

It is a circuit diagram which illustrates the composition of the receiving device of a 1st embodiment of the present invention. It is a figure which illustrates various signals used for the receiving device of a 1st embodiment. It is a circuit diagram which illustrates the composition of the receiving device of a 2nd embodiment of the present invention. It is a figure which illustrates various signals used for the receiver of a 2nd embodiment. It is a circuit diagram which illustrates the composition of the receiving device of the conventional example. It is a circuit diagram which illustrates the composition of the receiving device of the conventional example.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Antenna 11 Bandpass filter 12 Amplifier 13 Quadrature demodulator 14 Local signal source 15 Bandpass filter 16 Reception amplifier (variable amplifier)
18 Quadrature Demodulator 19 Local Signal Source 20 Band Pass Filter 21 A / D Converter 22 Reception Baseband Unit (RXBB)
23 CONT 24 Log Amplifier (LogAMP)
25 Loop filter 26 Switch (SW)
27 D / A Converter 28 Arithmetic Circuit (CAL)
29 Selector (SEL)

Claims (8)

A reception control method for digitally converting and demodulating an analog signal received by an antenna in a mobile station,
A first step of grasping a moving speed of the mobile station;
When the grasped moving speed is equal to or higher than a predetermined threshold, the gain of the receiving amplifier is controlled based on the received electric field strength of the analog signal received by the antenna, and the moving speed is less than the predetermined threshold. In this case, a reception control method comprising: a second step of digitally converting the analog signal and controlling a gain of the reception amplifier based on a reception electric field strength of the digitally converted reception signal. In a communication apparatus that performs communication using an adaptive modulation method, a reception control method for demodulating an analog signal received by an antenna by digital conversion,
A first step of grasping a modulation method of the communication device;
When the grasped modulation method is a modulation method that is less than a predetermined multi-value number, the gain of the reception amplifier is controlled based on the received electric field strength of the analog signal received by the antenna, and the modulation method is A second step of controlling the gain of the reception amplifier based on the received electric field strength of the digitally converted received signal after digitally converting the analog signal when the modulation method exceeds a predetermined multi-valued number; The reception control method characterized by including. In a mobile station that performs communication using an adaptive modulation scheme, a reception control method for digitally converting and demodulating an analog signal received by an antenna,
A first step of grasping a moving speed and a modulation method of the mobile station;
When the grasped moving speed is equal to or higher than a predetermined threshold and the modulation method of the mobile station is a modulation method that does not satisfy a predetermined multi-value number, the received electric field strength of the analog signal received by the antenna is Based on the gain of the receiving amplifier, and when the moving speed is less than the predetermined threshold and the modulation scheme of the mobile station exceeds the predetermined multi-level number, the analog signal is And a second step of controlling the gain of the reception amplifier based on the received electric field strength of the digitally converted received signal. In a receiving apparatus in a mobile station that demodulates an analog signal received by an antenna by digital conversion,
First receiving amplifier control means for controlling the gain of the receiving amplifier based on the received electric field strength of the analog signal received by the antenna;
Second receiving amplifier control means for digitally converting the analog signal received by the antenna and controlling the gain of the receiving amplifier based on the received electric field strength of the digitally converted received signal;
A moving speed acquisition means for acquiring information on the moving speed of the mobile station;
Based on the acquired information on the moving speed, when the moving speed is equal to or higher than a predetermined threshold, the gain of the receiving amplifier is controlled by the first receiving amplifier control means, and the moving speed is set to the predetermined threshold. And a reception amplifier control switching means for controlling a gain of the reception amplifier by the second reception amplifier control means when the second reception amplifier control means is less than the value. In a receiving apparatus that performs communication using an adaptive modulation method and digitally converts and demodulates an analog signal received by an antenna,
First receiving amplifier control means for controlling the gain of the receiving amplifier based on the received electric field strength of the analog signal received by the antenna;
Second receiving amplifier control means for digitally converting the analog signal received by the antenna and controlling the gain of the receiving amplifier based on the received electric field strength of the digitally converted received signal;
Modulation scheme acquisition means for acquiring information on the modulation scheme of the mobile station;
When the acquired modulation scheme is a modulation scheme that is less than a predetermined multi-value number, the first reception amplifier control means controls the gain of the reception amplifier, and the modulation method is the predetermined multi-value number. And a receiving amplifier control switching means for controlling the gain of the receiving amplifier by the second receiving amplifier control means. In a receiving apparatus in a mobile station that performs communication using an adaptive modulation scheme and demodulates an analog signal received by an antenna by digital conversion,
First receiving amplifier control means for controlling the gain of the receiving amplifier based on the received electric field strength of the analog signal received by the antenna;
Second receiving amplifier control means for digitally converting the analog signal received by the antenna and controlling the gain of the receiving amplifier based on the received electric field strength of the digitally converted received signal;
A moving speed acquisition means for acquiring information on the moving speed of the mobile station;
Modulation scheme acquisition means for acquiring information on the modulation scheme of the mobile station;
When the acquired moving speed is equal to or higher than a predetermined threshold and the acquired modulation scheme is a modulation scheme that does not satisfy a predetermined multi-value number, the gain of the reception amplifier is controlled by the first reception amplifier control means. When the acquired moving speed is less than the predetermined threshold value and the acquired modulation method is a modulation method exceeding the predetermined multi-value number, the second receiving amplifier control means And a receiving amplifier control switching means for controlling a gain of the receiving amplifier. The first reception amplifier control means includes a loop filter.
When the moving speed acquired by the moving speed acquisition means is greater than or equal to a predetermined threshold, the time constant of the loop filter is controlled to be relatively small, and the moving speed is less than the predetermined threshold 7. The receiving apparatus according to claim 4, wherein the time constant of the loop filter is controlled to be relatively large. The first reception amplifier control means includes a loop filter.
When the modulation scheme acquired by the modulation scheme acquisition means is a modulation scheme that does not satisfy a predetermined multi-value number, the time constant of the loop filter is controlled to be relatively small, and the modulation scheme is predetermined. 7. The receiving apparatus according to claim 5, wherein when the modulation method exceeds a multi-value number, the time constant of the loop filter is controlled to be relatively large.

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