JP5664388B2 - Portable wireless communication device - Google Patents

Description

  The present invention relates to a portable wireless communication device.

  In recent years, in portable wireless communication devices, particularly mobile phones, batteries have been downsized to improve portability. Also, in portable wireless communication devices, particularly mobile phones, application software used for realizing various functions has been rapidly increasing. In this way, the battery is downsized and the capacity that can be used is limited. By using various application software, more power is consumed, and as a circuit of the wireless unit in the portable wireless communication device, There has been a demand for further lower power consumption.

  Here, a wireless unit of a portable wireless communication device that requires low power consumption will be described. The portable wireless communication device has a function of adjusting the amplification gain of the reception signal because the reception level of the reception signal changes depending on the communication state. Then, the portable wireless communication device executes steps of frequency lock, AGC (Auto Gain Control) pull-in, reception level report value calculation and report, and data demodulation. The frequency lock is a process of converging the frequency of the received signal to the frequency of the baseband band. The AGC pull-in is a process in which the gain of the amplifier is changed based on the next reception level report value of the received signal and the gain of the amplifier is converged to an appropriate value. The calculation and reporting of the reception level report value is a step of acquiring the reception signal amplified by the amplifier in the AGC acquisition, calculating the reception level, and reporting the calculated value to the baseband processing unit. Data demodulation is a process of demodulating an input signal using an amplifier whose gain is adjusted after adjusting the gain of the amplifier to an appropriate value.

  The following techniques are known as conventional techniques for realizing low power consumption in such portable wireless communication devices. For example, during the frequency lock, AGC pull-in, and reception level report value calculation and reporting steps, the data demodulating circuit does not perform data demodulation. Therefore, a conventional technique has been proposed in which a data demodulating unit that performs data demodulation is paused during the steps of frequency lock, AGC pull-in, and reception level report value calculation and reporting.

JP 2005-130203 A

  However, in the prior art in which the data demodulator is suspended, circuits that consume the same power as the data demodulator, such as a measurement ADC (Analog Digital Converter) and a level detection circuit, are active. For this reason, it has been difficult for the conventional technique in which the data demodulating unit is suspended to sufficiently obtain the effect of reducing the power consumption.

  The disclosed technology has been made in view of the above, and an object thereof is to provide a portable wireless communication device that reduces power consumption.

  In one aspect, the mobile wireless communication device disclosed in the present application includes a first amplifier having a variable gain, and generates a first baseband signal from the input signal. The second RF unit includes a second amplifier having a variable gain, and generates a second baseband signal from the input signal. The gain adjusting unit calculates an appropriate gain based on the reception level of the first baseband signal generated by the first RF unit, and sets the gains of the first amplifier and the second amplifier to the appropriate gain. The baseband processing unit includes the first baseband signal generated by the first RF unit including the first amplifier having a gain set to the appropriate gain, and the second amplifier having the gain set to the appropriate gain. Data demodulation processing is performed on the second baseband signal generated by the second RF unit. The power supply control unit stops supplying power to the second RF unit until an appropriate gain is calculated by the gain adjustment unit.

  According to one aspect of the portable wireless communication device disclosed in the present application, there is an effect that power consumption can be reduced.

FIG. 1 is a block diagram of the mobile phone according to the first embodiment. FIG. 2 is a receiving circuit operation timing chart. FIG. 3 is a flowchart illustrating processing of calculating an appropriate gain and demodulating data in the mobile phone according to the first embodiment. FIG. 4 is a block diagram of the mobile phone according to the second embodiment. FIG. 5 is a flowchart illustrating processing of calculating an appropriate gain and demodulating data in the mobile phone according to the second embodiment. FIG. 6 is a hardware configuration diagram of the mobile phone.

  Embodiments of a portable wireless communication device disclosed in the present application will be described below in detail with reference to the drawings. The portable wireless communication device disclosed in the present application is not limited by the following embodiments. In particular, in the following description, a mobile phone will be described as an example, but this may be another portable wireless communication device. For example, the portable wireless communication device may be a PDA (Personal Data Assistant).

  FIG. 1 is a block diagram of the mobile phone according to the first embodiment. As shown in FIG. 1, a mobile phone 100 according to this embodiment includes an antenna 1, a BPF (Band Pass Filter) 2, an LNA (Low Noise Amplifier) 3, and an I (In-Phase) side RF (Radio Frequency) unit 4. , Q (Quadrature) side RF unit 5 and local oscillator 6. Furthermore, the mobile phone 100 according to the present embodiment includes ADCs 7, ADCs 8, a gain adjustment unit 9, a baseband processing unit 10, a BB (Base Band) side control unit 11, and an RF side control unit 12.

  BPF2 is a bandpass filter for band limitation. The BPF 2 passes only a predetermined frequency band in a radio frequency reception signal received via the antenna 1 and reduces unnecessary out-of-band noise. Then, the BPF 2 outputs the reception signal subjected to the band limitation to the LNA 3.

  The LNA 3 is a low noise amplifier. The LNA 3 receives an input of a reception signal subjected to band limitation from the BPF 2. Then, the LNA 3 amplifies the received signal. Then, the LNA 3 outputs the amplified received signal to the I-side RF unit 4 and the Q-side RF unit 5.

  The local oscillator 6 includes a phase shifter 61 and a PLL (Phase Lock Loop) synthesizer 62.

  The PLL synthesizer 62 receives an oscillation signal generation command having a local frequency shifted from a predetermined frequency by a predetermined frequency from the RF side control unit 12 described later at the start timing. Here, in this embodiment, the predetermined frequency plus the offset of 100 to 200 KHz is described as the local frequency shifted from the predetermined frequency by a predetermined frequency. Then, the PLL synthesizer 62 generates an oscillation signal having a local frequency obtained by adding an offset of 100 to 200 KHz to a predetermined frequency. Then, the PLL synthesizer 62 outputs the generated oscillation signal to the phase shifter 61.

  Here, the reason for shifting the local frequency at the time of activation will be described. With respect to the I signal and the Q signal, both reception levels do not become 0 at the same timing. However, in this embodiment, since the Q signal is not output from the Q-side RF unit 5 until the gains of the VGA (Variable Gain Amplifier) 43 and the VGA 53 are set to appropriate gains as described later, neither the I signal nor the Q signal is output. In both cases, a state of no input occurs. If no signal is input, the AGC calculation unit 92 determines that the reception level is 0, and increases the gains of the VGA 43 and VGA 53 more and more. Therefore, by shifting the predetermined frequency by a predetermined frequency, the AGC calculation unit 92 can measure the reception level of the shift even when there is no signal input, and it is determined that the reception level is 0 and the AGC calculation is performed. It can be avoided that the portion 92 increases the gain.

  The PLL synthesizer 62 receives an oscillation signal generation command having a predetermined frequency from the RF-side control unit 12 described later after a predetermined time T has elapsed from the activation timing. The predetermined time T will be described later in detail. Then, the PLL synthesizer 62 generates an oscillation signal having a predetermined frequency. Then, the PLL synthesizer 62 outputs the generated oscillation signal to the phase shifter 61.

  The phase shifter 61 receives an oscillation signal input from the PLL synthesizer 62. Then, the phase shifter 61 outputs the received oscillation signal to the I-side RF unit 4 as it is. The phase shifter 61 shifts the phase of the received oscillation signal by 90 degrees. Then, the phase shifter 61 outputs an oscillation signal whose phase is shifted by 90 degrees to the Q-side RF unit 5.

  As shown in FIG. 1, the I-side RF unit 4 includes a mixer 41, an LPF 42, and a VGA 43. The I-side RF unit 4 is an example of a “first RF unit”.

  The mixer 41 is a frequency converter. The mixer 41 receives an input of the reception signal from the LNA 3. Further, the mixer 41 receives an input of an oscillation signal having a phase oscillated from the PLL synthesizer 62 from the phase shifter 61. Then, the mixer 41 applies an oscillation signal to the reception signal. Then, the mixer 41 mixes the received signal and the oscillation signal, thereby converting the frequency of the received signal to the frequency of the baseband signal. In this embodiment, the mixer 41 down-converts the received signal. At this time, since the phase of the oscillation signal is the same as the phase oscillated by the PLL synthesizer 62, the mixer 41 generates an I signal that is a baseband signal of the in-phase component of the reception signal. Here, the I signal corresponds to an example of a “first baseband signal”. In particular, an I signal generated using an oscillation signal having a local frequency obtained by adding an offset of 100 to 200 KHz to a predetermined frequency is an example of an “adjustment baseband signal”. Then, the mixer 41 outputs the I signal to the LPF 42.

  The LPF 42 is a low-pass filter. The LPF 42 receives an I signal input from the mixer 41. The LPF 42 limits the band of the received I signal, and removes unnecessary noise such as adjacent channel signals and harmonics included in the I signal. Then, the LPF 42 outputs the filtered I signal to the VGA 43.

  The VGA 43 is a variable gain amplifier. The VGA 43 is set with an initial value of a predetermined gain. The initial value may be output by the gain adjusting unit 9 until the appropriate gain is calculated. The VGA 43 receives a VGA variable signal for changing the gain to an appropriate gain from the gain adjusting unit 9 described later. Then, the VGA 43 sets its own gain to an appropriate gain specified by the received VGA variable signal.

  The VGA 43 receives an input of the filtered I signal from the LPF 42. The VGA 43 amplifies the I signal with the set gain. Here, when the VGA 43 does not receive the VGA variable signal from the gain adjusting unit 9, the VGA 43 amplifies the I signal with the initial gain. Further, when the VGA 43 receives a VGA variable signal for setting an appropriate gain from the gain adjusting unit 9, the VGA 43 amplifies the I signal with an appropriate gain designated by the VGA variable signal. Then, the VGA 43 outputs the amplified I signal to the ADC 7. The VGA 43 is an example of a “first amplifier”.

  The ADC 7 is an analog / digital converter. The ADC 7 receives an input of the amplified I signal from the VGA 43. The ADC 7 converts the received I signal into a digital signal. Then, the ADC 7 outputs the I signal converted into the digital signal to the baseband processing unit 10. Further, the ADC 7 outputs the I signal converted into the digital signal to the gain adjusting unit 9. The ADC 7 is an example of “first ADC”.

  As shown in FIG. 1, the Q-side RF unit 5 includes a mixer 51, an LPF 52, and a VGA 53. As will be described later, the Q-side RF unit 5 is not supplied with power until the VGA 43 and the VGA 53 receive the VGA variable signal after being activated. That is, the Q-side RF unit 5 does not operate until the VGA 43 and the VGA 53 receive the VGA variable signal after the activation. Therefore, the operation of the Q-side RF unit 5 in the following description is an operation after the VGA 43 and the VGA 53 receive the VGA variable signal. The Q-side RF unit 5 corresponds to an example of a “second RF unit”.

  The mixer 51 is a frequency converter. The mixer 51 receives an input of the reception signal from the LNA 3. Further, the mixer 51 receives from the phase shifter 61 an input of an oscillation signal whose phase is shifted by 90 degrees from the state oscillated from the PLL synthesizer 62. Then, the mixer 51 applies an oscillation signal whose phase is shifted by 90 degrees with respect to the reception signal. Then, the mixer 51 mixes the reception signal and the oscillation signal to convert the frequency of the reception signal to the frequency of the baseband signal. In this embodiment, the mixer 51 down-converts the received signal. At this time, since the phase of the oscillation signal is shifted 90 degrees from the phase oscillated by the PLL synthesizer 62, the mixer 51 generates a Q signal that is a baseband signal of the quadrature component of the received signal. . The Q signal corresponds to an example of a “second baseband signal”. Then, the mixer 51 outputs the Q signal to the LPF 52.

  The LPF 52 is a low-pass filter. The LPF 52 receives the Q signal from the mixer 51. Then, the LPF 52 limits the band of the received Q signal, and removes unnecessary noise such as adjacent channel signals and harmonics included in the Q signal. Then, the LPF 52 outputs the filtered Q signal to the VGA 53.

  The VGA 53 is a variable gain amplifier. The VGA 53 receives a VGA variable signal for setting the gain to an appropriate gain from a gain adjusting unit 9 described later. The VGA 53 sets its own gain to an appropriate gain specified by the received VGA variable signal.

  The VGA 53 receives an input of the filtered Q signal from the LPF 52. The VGA 53 amplifies the Q signal with the set gain. Here, since the VGA 53 receives the VGA variable signal for setting an appropriate gain from the gain adjustment unit 9, the VGA 53 amplifies the Q signal with an appropriate gain designated by the VGA variable signal. Then, the VGA 53 outputs the amplified Q signal to the ADC 8.

  The ADC 8 is an analog / digital converter. The ADC 8 receives an input of the amplified Q signal from the VGA 53. The ADC 8 converts the received Q signal into a digital signal. Then, the ADC 8 outputs the Q signal converted into the digital signal to the baseband processing unit 10. Further, the ADC 8 outputs the Q signal converted into the digital signal to the gain adjusting unit 9. The ADC 8 is an example of a “second ADC”.

  The gain adjustment unit 9 includes a level detection unit 91, an AGC calculation unit 92, and a level detection unit 93. Here, as will be described later, the level detection unit 93 is not supplied with power until the VGA 43 and the VGA 53 receive the VGA variable signal after being activated. That is, the level detection unit 93 does not operate until the VGA 43 and the VGA 53 receive the VGA variable signal after activation. Therefore, the operation of the level detection unit 93 in the following description is an operation after the VGA 43 and the VGA 53 receive the VGA variable signal.

  The level detection unit 91 receives an input of the I signal converted into the digital signal from the ADC 7. Then, the level detection unit 91 acquires information on the reception level of the I signal from the amplitude of the received I signal. Then, the level detection unit 91 outputs the acquired information on the reception level of the I signal to the AGC calculation unit 92. The level detection unit 91 is an example of a “first reception level detection unit”.

  The level detection unit 93 receives the input of the Q signal converted into the digital signal from the ADC 8. Then, the level detector 93 acquires information on the reception level of the Q signal from the amplitude of the received Q signal. Then, the level detection unit 93 outputs the acquired information on the reception level of the Q signal to the AGC calculation unit 92. The level detection unit 93 corresponds to an example of a “second reception level detection unit”.

The AGC calculation unit 92 stores (2 × VI ² ) ^1/2 in advance as a calculation formula for obtaining a received signal strength indicator (RSSI) from the reception level of the I signal. Here, VI is the reception level of the I signal. The AGC calculation unit 92 stores (VQ ² + VI ² ) ^1/2 in advance as a calculation formula for obtaining RSSI from the reception level of the I signal and the reception level of the Q signal. Here, VQ is the reception level of the Q signal.

After being activated, the AGC calculation unit 92 receives a command for calculating an appropriate gain from the RF side control unit 12 described later. Then, the AGC calculation unit 92 receives an input of VI which is reception level information only from the level detection unit 91. Then, the AGC calculation unit 92 calculates RSSI as (2 × VI ² ) ^1/2 from the received VI. Then, the AGC calculation unit 92 obtains an appropriate gain from the calculated RSSI. Here, the appropriate gain is a gain by which each of the I signal and the Q signal is amplified by the ADC 7 and the ADC 9 to a level that enters a good dynamic range. The calculation of the appropriate gain is performed, for example, when the AGC calculation unit 92 obtains the appropriate gain corresponding to the calculated RSSI value using a table in which the correspondence between the RSSI value and the appropriate gain is described. . Then, the AGC calculation unit 92 generates a VGA variable signal that notifies the obtained appropriate gain. Then, the AGC calculation unit 92 outputs the generated VGA variable signal to the VGA 43 and the VGA 53.

In addition, the AGC calculation unit 92 receives an RSSI calculation start command using the I signal and the Q signal from the RF-side control unit 12 after a predetermined time T has elapsed after receiving the command for calculating the appropriate gain. Then, the AGC calculation unit 92 starts calculating RSSI using the I signal and the Q signal. At this time, the AGC calculation unit 92 receives VI, which is the reception level of the I signal, and VQ, which is the reception level of the Q signal, from the level detection unit 91 and the level detection unit 93, respectively. Then, the AGC calculation unit 92 calculates RSSI as (VQ ² + VI ² ) ^1/2 from the reception levels of the received I signal and Q signal. Then, the AGC calculation unit 92 outputs the calculated RSSI value to the baseband processing unit 10. The AGC calculation unit 92 is an example of a “gain calculation unit”.

  The baseband processing unit 10 includes a BB side control unit 11.

  The BB side control unit 11 stores a predetermined time T determined in advance. The predetermined time is the time from when the VGA variable signal for notifying the VGA 43 and the VGA 53 to the appropriate gain is output after the activation. The predetermined time T is preferably determined according to the configuration of the circuit here. In this embodiment, since the time from the start to the output of the VGA variable signal is considered to be fixed for each circuit, the operation timing is controlled by setting the time as the predetermined time T. Other methods may be used. For example, even if the BB side control unit 11 receives the RSSI value from the AGC calculation unit 92 during the AGC pull-in, determines whether the RSSI converges from the movement of the RSSI value, and controls to move to the next operation. good.

  Further, the BB side control unit 11 stores time slots in advance. Then, at the start timing of the time slot stored in advance, the BB side control unit 11 notifies the RF side control unit 12 of an activation command. At this time, the BB side control unit 11 notifies the RF side control unit 12 of a command to stop supplying power to the Q side RF unit 5, the ADC 8, and the Level detection unit 93. Furthermore, the BB side control unit 11 also stops supplying power to the baseband processing unit 10. At this time, the BB side control unit 11 performs control so that power is supplied to the baseband processing unit 10 after a predetermined time T has elapsed.

  When the supply of power is stopped by the BB side control unit 11, the baseband processing unit 10 stops its operation. Then, when the predetermined time T has elapsed, the supply of power to the baseband processing unit 10 is resumed, and the operation of the baseband processing unit 10 is resumed. Then, the baseband processing unit 10 receives an I signal input from the ADC 7. The baseband processing unit 10 receives an input of the Q signal from the ADC 8. Then, the baseband processing unit 10 performs phase detection on the received I signal and Q signal and performs data demodulation. Then, the baseband processing unit 10 outputs the demodulated data using a display unit, an audio output unit (both not shown), and the like.

  The RF side control unit 12 receives an activation command from the BB side control unit 11. At this time, the RF-side control unit 12 also receives an instruction to stop supplying power to the Q-side RF unit 5, the ADC 8, and the Level detection unit 93. Then, the RF side control unit 12 instructs the power supply control unit 13 to supply power to other than the Q side RF unit 5, the ADC 8, and the Level detection unit 93. Further, the RF-side control unit 12 transmits a command for calculating an appropriate gain to the AGC calculation unit 92.

  Moreover, the RF side control part 12 has memorize | stored the predetermined time T decided beforehand. Then, when a predetermined time T elapses after receiving the activation command, the RF side control unit 12 instructs the power supply control unit 13 to supply power to the Q side RF unit 5, the ADC 8, and the Level detection unit 93.

  Further, the RF-side control unit 12 instructs the AGC calculation unit 92 to calculate RSSI using the I signal and the Q signal when a predetermined time T has elapsed after receiving the activation command. Further, the RF side control unit 12 instructs the local oscillator 6 to output an oscillation signal having a predetermined frequency. Further, the RF-side control unit 12 transmits an RSSI calculation start command using the I signal and the Q signal to the AGC calculation unit 92 after a predetermined time T has elapsed after receiving the activation command.

  In this embodiment, only the start timing signal is received from the BB side control unit 11 and the RF side control unit 12 uses the predetermined time T to control the frequency shift and power supply in the local oscillator 6. Yes, but this can be done in other ways. For example, the BB side control unit 11 may send a timing signal at each timing, and the RF side control unit 12 may autonomously control accordingly. As another example, the following method may be used. That is, the BB side control unit 11 issues a command that triggers frequency shift and power supply in the local oscillator 6. Then, the RF side control unit 12 may be controlled by inputting a command issued from the BB side control unit 11 to the RF side control unit 12 via an interface such as a serial 3-wire.

  The power supply control unit 13 receives an instruction to supply power from the RF side control unit 12 to other than the Q side RF unit 5, the ADC 8, and the level detection unit 93 at the start timing. Then, the power supply control unit 13 starts supplying power to the BPF 2, LNF 3, I-side RF unit 4, local oscillator 6, ADC 7, Level detection unit 91, and AGC calculation unit 92. At this time, the power supply control unit 13 performs control so that power is not supplied to the mixer 51, the LPF 52, and the VGA 53, for example, as stopping the power supply to the Q-side RF unit 5. That is, the stoppage of power supply represents suppression of power supply so as not to supply power to each unit, for example. Here, in FIG. 1, in order to make the drawing easier to see, arrows for supplying electric power from the power supply control unit 13 only to each unit that is the target of stopping the electric power supply are shown. There is a path for supplying power from the power supply control unit 13 to all of the units.

  The power supply control unit 13 receives an instruction to supply power from the RF-side control unit 12 to the Q-side RF unit 5, the ADC 8, and the Level detection unit 93 after a predetermined time has elapsed from the activation timing. Then, the power supply control unit 13 starts supplying power from the RF side control unit 12 to the Q side RF unit 5, the ADC 8, and the Level detection unit 93.

  Next, with reference to FIG. 2, the flow of operation of each unit will be described in time series. FIG. 2 is a receiving circuit operation timing chart. FIG. 2 shows that time passes as it goes to the right toward the page. The dotted line represents the timing on the time series, and the arrow between the dotted lines represents the time range. Time 201 is the activation timing. Times 202, 203, 204, and 206 represent times for performing the processes a, b, c, and d, respectively. Time 205 is the timing when the process c ends. The time obtained by combining the times 202, 203, and 204, that is, the time from time 201 to time 205 corresponds to the predetermined time T described above.

  At time 201, the BB side control unit 11 detects the start of the time slot and notifies the RF side control unit 12 of an activation command. Then, the RF-side control unit 12 notifies the power supply control unit 13 of a power supply command to other than the Q-side RF unit 5, the ADC 8, and the level detection unit 93. The power supply control unit 13 starts supplying power to each unit other than the Q-side RF unit 5, the ADC 8, and the Level detection unit 93. At this time, the power supply to the baseband processing unit 10 is also stopped by the BB side control unit 11.

  At time 202, process a for performing frequency lock is executed. Specifically, the I-side RF unit 4 receives a reception signal that passes through the antenna 1, the BPF 2, and the LNA 3. Further, the mixer 41 receives an oscillation signal having a frequency obtained by adding an offset of 100 to 200 KHz to the predetermined frequency from the local oscillator 6. Then, the mixer 41 applies an oscillation signal to the reception signal, thereby converting the reception signal to a frequency obtained by adding an offset of 100 to 200 KHz to the baseband frequency.

  At the next time 203, the process b for generating the VGA variable signal for setting the AGC pull-in and the appropriate gain is executed. Specifically, first, the LPF 42 filters the I signal output from the mixer 41 to remove unnecessary noise. Next, the VGA 43 amplifies the I signal using the gain of the initial value. The I signal amplified with the initial gain is converted into a digital signal by the ADC 7 and input to the level detection unit 91. Then, the level detector 91 detects the reception level of the I signal. Using the detected reception level of the I signal, the AGC calculation unit 92 obtains an appropriate gain. Then, the AGC calculation unit 92 generates a VGA variable signal that sets an appropriate gain.

  At the next time 204, processing c for notifying the RSSI value and setting an appropriate gain is executed. Specifically, the AGC calculation unit 92 notifies the baseband processing unit 10 of the calculated RSSI value. Further, the AGC calculation unit 92 outputs the generated VGA variable signal for setting the appropriate gain to the VGA 43 and the VGA 53.

  Then, at time 205, which is the completion timing of the process c, the RF-side control unit 12 notifies the power supply control unit 13 of a power supply command to the Q-side RF unit 5, ADC 8, and Level detection unit 93. The power supply control unit 13 starts supplying power to the Q-side RF unit 5, the ADC 8, and the Level detection unit 93.

  At the next time 206, data demodulation processing d is performed. The I-side RF unit 4 and the Q-side RF unit 5 receive a received signal input via the antenna 1, BPF 2, and LNA 3. The local oscillator 6 oscillates an oscillation signal having a predetermined frequency. The oscillation signal from the local oscillator 6 is input to the mixer 41 as it is. On the other hand, the oscillation signal from the local oscillator 6 whose phase is shifted by 90 degrees by the phase shifter 61 is input to the mixer 51. Then, the mixer 41 converts the frequency of the received signal into a baseband frequency using the oscillation signal, and generates an I signal. On the other hand, the mixer 51 converts the frequency of the received signal into a baseband frequency using an oscillation signal whose phase is shifted by 90 degrees, and generates a Q signal. The I signal is filtered by the LPF 42, amplified by an appropriate gain in the VGA 43, converted to a digital signal, and output to the baseband processing unit 10. The Q signal is filtered by the LPF 52, amplified by the VGA 53 with an appropriate gain, converted to a digital signal, and output to the baseband processing unit 10. Then, power supply to the baseband processing unit 10 is resumed. Then, the baseband processing unit 10 performs demodulation processing on the received I signal and Q signal. Then, the baseband processing unit 10 outputs the demodulated data using a display unit, an audio output unit, or the like.

  Then, at time 207, the receiving circuit of the mobile phone 100 stops processing.

  As described here, in the mobile phone 100 according to the present embodiment, the Q-side RF unit 5, the ADC 8, and the Level detection unit 93 are between the times 202, 203, and 204, that is, from the time 201 to the time 205. The power is not supplied to. Therefore, power consumption between time 201 and time 205 can be reduced.

  Here, FIG. 2 has been described in a state where data is demodulated after notification of appropriate gain. However, if the mobile phone 100 does not receive a data signal at this timing, data demodulation is not performed. Pause until time slot. That is, if there is no reception of the data signal, the processing from the processing a to the processing c is repeated, and in the meantime, almost half of the power can be reduced.

  Further, considering the reduction of power only by the processing described in FIG. 2, the processing a to processing c is about 10% of the time from time 201 to time 205. Therefore, in the process described in FIG. 2, by not supplying power to the Q-side RF unit 5, ADC 8 and Level detection unit 93 from time 201 to time 205, 5% of the power of the entire process is obtained. Can be reduced.

  Next, with reference to FIG. 3, the flow of the calculation of the aptitude gain and the data demodulation in the mobile phone according to the present embodiment will be described. FIG. 3 is a flowchart illustrating processing of calculating an appropriate gain and demodulating data in the mobile phone according to the first embodiment.

  The BB side control unit 11 detects the start of the time slot. Then, the BB side control unit 11 notifies the RF side control unit 12 of the start command and the supply stop of power to the Q side RF unit 5, the ADC 8 and the Level detection unit 93. The RF-side control unit 12 notifies the power supply control unit 13 of a power supply command to other than the Q-side RF unit 5, the ADC 8, and the level detection unit 93. The power supply control unit 13 stops supplying power to the Q-side RF unit 5, ADC 8 and Level detection unit 93, and starts supplying power to other than the Q-side RF unit 5, ADC 8 and Level detection unit 93. At this time, the power supply to the baseband processing unit 10 is also stopped by the BB side control unit 11 (step S101).

  The local oscillator 6 and the mixer 41 perform frequency lock on the received signal at a frequency obtained by adding an offset of 100 to 200 KHz to a predetermined frequency to generate an I signal (step S102).

  Using the adjustment signal, the I-side RF unit 4, ADC 7, Level detection unit 91, and AGC calculation unit 92 perform AGC pull-in, calculate RSSI, and obtain an appropriate gain (step S103). Then, the AGC calculation unit 92 generates a VGA variable signal that sets the obtained appropriate gain.

  The AGC calculation unit 92 notifies the obtained RSSI value to the baseband processing unit 10 (step S104).

  When a predetermined time T elapses after the start-up command is received from the BB-side control unit 11, the RF-side control unit 12 issues a power supply command to the Q-side RF unit 5, ADC 8 and Level detection unit 93. Notify The power supply control unit 13 starts supplying power to the Q-side RF unit 5, the ADC 8, and the Level detection unit 93 (step S105).

  Using the oscillation signal of the predetermined frequency output from the local oscillator 6, the mixer 41 and the mixer 51 perform frequency lock on the reception signal at the predetermined frequency, and generate an I signal and a Q signal, respectively (step S106).

  The VGA 43 performs amplification with an appropriate gain set for the I signal that has passed through the filter 42. Further, the VGA 53 performs amplification with the appropriate gain set for the Q signal that has passed through the filter 52 (step S107).

  The baseband processing unit 10 is set so that the power supply is resumed after a predetermined time T has elapsed from the stop of the power supply by the BB side control unit 11. Therefore, supply of power to the baseband processing unit 10 is started (step S108).

  Then, the baseband processing unit 10 performs data demodulation processing on the input I signal and Q signal (step S109).

  As described above, the portable wireless communication apparatus according to the present embodiment is configured to generate the Q signal (hereinafter referred to as “Qch side”) while adjusting the gain of the variable gain amplifier to an appropriate value. The RF unit, ADC, and Level detection unit are not supplied with power. Therefore, power consumption while adjusting the gain of the variable gain amplifier to an appropriate value can be reduced, and power consumption of the portable wireless communication device can be reduced. In particular, many mixers, LPFs, VGAs, ADCs, and Level detection units are analog circuits that occupy most of the power in the receiving circuit. Therefore, halving the power consumption in these circuits has the effect of reducing power consumption. For example, when a general RFLSI circuit design technique is used, in the mobile phone according to the present embodiment, if the total current consumption is 50 mA, the current consumption of about 15 to 20 mA is reduced. Further, for example, at the time of standby in the W-CDMA system, reduction of power consumption can be realized in a section of 10% of the reception operation.

  FIG. 4 is a block diagram of the mobile phone according to the second embodiment. The cellular phone 100 according to the present embodiment is different from the first embodiment in that a load circuit is provided so as to have the same impedance as that when power is supplied even when power is not supplied. Therefore, in the following description, the configuration of the load circuit and switching to the load circuit will be mainly described. Here, in FIG. 4, each part which has the same code | symbol as FIG. 1 shall have the same function unless there is particular description.

  As shown in FIG. 4, the mobile phone 100 according to the present embodiment further includes a switch 14, a switch 15, a load circuit 16, and a load circuit 17 in addition to the mobile phone of the first embodiment shown in FIG. .

  The switch 14 is provided between the LNA 3 and the mixer 51. The switch 14 switches between a path connecting the LNA 3 and the mixer 51 and a path connecting the LNA 3 and the load circuit 16. When the switch 14 is switched to the mixer 51 side, the signal output from the LNA 3 is input to the mixer 51. On the other hand, when the switch 14 is switched to the load circuit 16 side, the signal output from the LNA 3 is input to the load circuit 16. The switch 14 is an example of a “first switch”.

  The load circuit 16 includes a coil 161 and a capacitor 162. The inductance of the coil 161 and the capacitance of the capacitor 162 are determined so that the impedance of the mixer 51 and the impedance of the load circuit 16 when power is supplied to the Q-side RF unit 5, ADC 8 and Level detection unit 93 are equal. ing. The load circuit 16 is an example of a “first load circuit”.

  The switch 15 is provided between the phase shifter 61 and the mixer 51. The switch 15 switches between a path connecting the phase shifter 61 and the mixer 51 and a path connecting the phase shifter 61 and the load circuit 17. When the switch 15 is switched to the mixer 51 side, the oscillation signal output from the phase shifter 61 is input to the mixer 51. On the other hand, when the switch 15 is switched to the load circuit 17 side, the oscillation signal output from the phase shifter 61 is input to the load circuit 17. The switch 15 is an example of a “second switch”.

  The load circuit 17 includes a coil 171 and a capacitor 172. The inductance of the coil 171 and the capacitance of the capacitor 172 are determined so that the impedance of the mixer 51 and the impedance of the load circuit 17 when power is supplied to the Q-side RF unit 5, ADC 8 and Level detection unit 93 are equal. ing. The load circuit 17 corresponds to an example of a “second load circuit”.

  The BB side control unit 11 notifies the start command to the RF side control unit 12 at the start timing of the time slot and also notifies the Q side RF unit 5, the ADC 8, and the Level detection unit 93 to stop power supply. Further, the BB side control unit 11 transmits a switching command to the load circuit 16 side of the switch 14 and a switching command to the load circuit 17 side of the switch 15 to the RF side control unit 12.

  The RF side control unit 12 receives from the BB side control unit 11 a start command, a command to stop power supply to each unit, and a switch command for the switch 14 and the switch 15.

  The RF-side control unit 12 notifies the power supply control unit 13 of an instruction to start power supply to other than the Q-side RF unit 5, the ADC 8, and the level detection unit 93. Then, the RF side control unit 12 switches the switch 14 to the load circuit 16 side. Further, the RF side control unit 12 switches the switch 15 to the load circuit 17 side. The RF side control unit 12 corresponds to an example of a “switch control unit”.

  Further, the RF side control unit 12 switches the switch 14 to the mixer 51 side after a predetermined time T has elapsed after receiving the activation command from the BB side control unit 11. Further, the RF side control unit 12 switches the switch 15 to the mixer 51 side. Then, the RF side control unit 12 notifies the power supply control unit 13 of an instruction to start power supply to the Q side RF unit 5, the ADC 8, and the Level detection unit 93.

  That is, the switch 14 is switched to the load circuit 16 side while the supply of power to the Q-side RF unit 5, ADC 8, and Level detection unit 93 is stopped. Similarly, the switch 15 is switched to the load circuit 17 side while the supply of power to the Q-side RF unit 5, ADC 8, and Level detection unit 93 is stopped. As a result, the switch 15 generates impedance similar to the state in which power is supplied even when power is not supplied to the Q-side RF unit 5, the ADC 8, and the level detection unit 93. The signal can be transmitted more accurately.

  Next, with reference to FIG. 5, the flow of the calculation of aptitude gain and data demodulation in the mobile phone according to the present embodiment will be described. FIG. 5 is a flowchart illustrating processing of calculating an appropriate gain and demodulating data in the mobile phone according to the second embodiment.

  The BB side control unit 11 detects the start of the time slot. Then, the BB side control unit 11 notifies the RF side control unit 12 of the start command and the supply stop of power to the Q side RF unit 5, the ADC 8 and the Level detection unit 93. Further, the BB side control unit 11 transmits a switching command to the load circuit 16 side of the switch 14 and a switching command to the load circuit 17 side of the switch 15 to the RF side control unit 12. The RF-side control unit 12 notifies the power supply control unit 13 of a power supply command to other than the Q-side RF unit 5, the ADC 8, and the level detection unit 93. The power supply control unit 13 stops supplying power to the Q-side RF unit 5, ADC 8 and Level detection unit 93, and starts supplying power to other than the Q-side RF unit 5, ADC 8 and Level detection unit 93. At this time, the power supply to the baseband processing unit 10 is also stopped by the BB side control unit 11 (step S201).

  Next, the RF side control unit 12 switches the switch 14 to the load circuit 16 side. Further, the RF side control unit 12 switches the switch 15 to the load circuit 17 side (step S202).

  The local oscillator 6 and the mixer 41 perform frequency lock on the received signal at a frequency obtained by adding an offset of 100 to 200 KHz to a predetermined frequency to generate an I signal (step S203).

  Using the adjustment signal, the I-side RF unit 4, ADC 7, Level detection unit 91, and AGC calculation unit 92 perform AGC pull-in, calculate RSSI, and obtain an appropriate gain (step S204). Then, the AGC calculation unit 92 generates a VGA variable signal that sets the obtained appropriate gain.

  The AGC calculation unit 92 notifies the baseband processing unit 10 of the obtained RSSI value (step S205).

  When a predetermined time T elapses after the start-up command is received from the BB-side control unit 11, the RF-side control unit 12 issues a power supply command to the Q-side RF unit 5, ADC 8 and Level detection unit 93. Notify The power supply control unit 13 starts supplying power to the Q-side RF unit 5, the ADC 8, and the Level detection unit 93 (step S206).

  Next, the RF side control unit 12 switches the switch 14 to the mixer 51 side. Further, the RF side control unit 12 switches the switch 15 to the mixer 51 side (step S207).

  Using the oscillation signal of the predetermined frequency output from the local oscillator 6, the mixer 41 and the mixer 51 perform frequency lock on the reception signal at the predetermined frequency to generate an I signal and a Q signal, respectively (step S208).

  The VGA 43 performs amplification with an appropriate gain set for the I signal that has passed through the filter 42. Further, the VGA 53 performs amplification with the appropriate gain set for the Q signal that has passed through the filter 52 (step S209).

  The baseband processing unit 10 is set so that the power supply is resumed after a predetermined time T has elapsed from the stop of the power supply by the BB side control unit 11. Therefore, supply of power to the baseband processing unit 10 is started (step S210).

  Then, the baseband processing unit 10 performs data demodulation processing on the input I signal and Q signal (step S211).

  As described above, the mobile phone according to the present embodiment is in a state where power is supplied even when power is not supplied to the RF unit, ADC, and Level detection unit on the Qch side. A similar impedance is generated. Thereby, in the mobile phone according to the present embodiment, the signal can be transmitted more accurately than in the first embodiment.

  In each of the above embodiments, power supply to the Q-side RF unit 5, ADC 8 and Level detection unit 93 (referred to as “Qch-side circuit”) is stopped, and the I-side RF unit 4, ADC 7 and Level detection unit. 91 (referred to as “Ich side circuit”) calculates RSSI. However, the side to stop the power supply may be reversed. That is, the power supply to the Ich side circuit may be stopped and the RSSI may be calculated on the Qch side. Even if it does in this way, the effect similar to each Example mentioned above is acquired.

  In each of the above embodiments, the supply of power to the Q-side RF unit 5, ADC 8, Level detection unit 93, and baseband processing unit 10 is stopped in order to reduce as much power consumption as possible. However, depending on the degree of demand for reduction in power consumption, it is not necessary to stop the power supply of any one of ADC 8, Level detection unit 93 and baseband processing unit 10, or a combination thereof. However, since the effect of reducing power consumption increases as the number of parts where power supply is stopped is increased, it is preferable to stop power supply to as many parts as possible.

[Mobile phone hardware configuration]
Next, a hardware configuration example of the mobile phone 100 will be described with reference to FIG. FIG. 6 is a hardware configuration diagram of the mobile phone.

  As shown in FIG. 6, the mobile phone 100 includes an antenna 1, an RF communication unit 101, a CPU (Central Processing Unit) 102, a memory 103, a voice input / output unit 104, a display unit 105, an input unit 106, a power control circuit 107, and A battery 108 is included. A dotted line extending from the power control circuit 107 to each part represents a power supply line.

  The RF communication unit 101, the memory 103, the voice input / output unit 104, the display unit 105, the input unit 106, and the power supply control circuit 107 are connected to the CPU 102. The antenna 1 is connected to the RF communication unit 101. The battery 108 is connected to the power control circuit 107.

  The RF communication unit 101 corresponds to, for example, the BPF 2, LNA 3, I-side RF unit 4, Q-side RF unit 5, local oscillator 6, ADCs 7 and 8, and gain adjustment unit 9 shown in FIG.

  The voice input / output unit 104 is, for example, a microphone and a speaker. The display unit 105 is a display screen, for example.

  The power control circuit 107 corresponds to, for example, the power control unit 13 in FIG. A power supply line is provided between the power supply control circuit 107 and each of the CPU 102, the memory 103, the audio input / output unit 104, the display unit 105, and the input unit 106. The battery 108 is a rechargeable battery, for example.

  For example, the CPU 102 and the memory 103 implement the functions of the baseband processing unit 10 shown in FIG. For example, the memory 103 stores various programs for realizing processing by the gain adjusting unit 9 and the baseband processing unit 10 illustrated in FIG. Then, the CPU 102 reads out and executes these programs stored in the memory 103, thereby generating a process that realizes each function described above. In this embodiment, the RF communication unit 101 includes a CPU and a sequencer. The function of the RF side control unit 12 is realized by the RF communication unit 101 and the memory 103. In this case, the memory 103 stores various programs for realizing processing by the RF-side control unit 12 illustrated in FIG. The RF communication unit 101 reads out and executes these programs stored in the memory 103, thereby generating a process for realizing the function of the RF-side control unit 12 described above.

1 Antenna 2 BPF (Band Pass Filter)
3 LNA (Low Noise Amplifier)
4 I side RF unit 5 Q side RF unit 6 Local oscillator 7, 8 ADC (Analog Digital Converter)
DESCRIPTION OF SYMBOLS 9 Gain adjustment part 10 Baseband process part 11 BB side control part 12 RF side control part 13 Power supply control part 14, 15 Switch 16, 17 Load circuit 41, 51 Mixer 42, 52 LPF (Low Pass Filter)
43, 53 VGA (Variable Gain Amplifier)
61 Phase shifter 62 PLL synthesizer 91, 93 Level detection unit 92 AGC calculation unit 161, 171 Coil 162, 172 Capacitor

Claims (8)

A first RF unit having a first amplifier with a variable gain, and generating a first baseband signal from the input signal;
A second RF unit having a second amplifier with a variable gain and generating a second baseband signal from the input signal;
A gain adjustment unit that calculates an appropriate gain based on a reception level of the first baseband signal generated by the first RF unit, and sets the gains of the first amplifier and the second amplifier to the appropriate gain;
A first baseband signal generated by the first RF unit having the first amplifier with the gain set to the appropriate gain and a second RF unit having the second amplifier with the gain set to the appropriate gain. A baseband processing unit for performing data demodulation processing on the second baseband signal;
A portable radio communication apparatus comprising: a power supply control unit that stops supplying power to the second RF unit until an appropriate gain is calculated by the gain adjustment unit. The first RF unit receives an adjustment signal and a data signal,
The second RF unit receives the data signal,
The gain adjustment unit calculates an appropriate gain of the first amplifier and the second amplifier based on the reception level of the first baseband signal generated from the adjustment signal by the first RF unit,
The baseband processing unit includes a first baseband signal generated from the data signal by the first RF unit having a first amplifier changed to the appropriate gain, and a second amplifier changed to the appropriate gain. Data demodulation processing is performed on the second baseband signal generated from the data signal by the second RF unit,
The power supply control unit stops supplying power to the second RF unit until an appropriate gain is calculated by the gain adjustment unit after at least the first RF unit receives the adjustment signal.
The portable radio communication apparatus according to claim 1. The gain adjuster is
A first reception level detection unit for detecting a reception level from the first baseband signal generated by the first RF unit;
A second reception level detection unit for detecting a reception level from the second baseband signal generated by the second RF unit;
Gain calculation for calculating the appropriate gain based on the reception level of the first baseband signal detected by the first reception level detector, and setting the gains of the first amplifier and the second amplifier to the appropriate gain With
The power supply control unit stops supplying power to the second RF unit and the second reception level detection unit until an appropriate gain is calculated by the gain adjustment unit. Portable wireless communication device. A first ADC for converting the first baseband signal into a digital signal;
A second ADC for converting the second baseband signal into a digital signal;
The gain adjusting unit calculates a reception level using the first baseband signal converted into a digital signal,
4. The power supply control unit further stops supplying power to the second ADC until an appropriate gain is calculated by the gain adjustment unit. 5. Portable wireless communication device. The second RF unit includes
A mixer that converts the input signal to a predetermined frequency based on a signal from a local oscillator;
LPF excluding the high frequency band of the output from the mixer section,
The second amplifier amplifies the signal output from the LPF,
The power supply control unit stops power supply to the second RF unit by stopping power supply to at least the mixer unit, the LPF, and the second amplifier. The portable wireless communication device according to any one of the above. A first switch that switches a path of an input signal to the second RF unit to either the second RF unit or the first load circuit;
A second switch that switches a path of a signal output from the local oscillator to either the second RF unit or the second load circuit;
The first switch is switched to the first load circuit side until the appropriate gain is calculated by the gain adjustment unit, the second switch is switched to the second load circuit side, and after the calculation of the appropriate gain by the gain adjustment unit The portable wireless communication device according to claim 5 , further comprising: a switch control unit that switches the first switch and the second switch to the second RF unit side.   The baseband processing unit generates the first baseband signal by the first RF unit having the first amplifier changed to the appropriate gain, and the second RF unit has the second amplifier changed to the appropriate gain. The portable wireless communication device according to claim 1, further comprising a control unit that stops power supply to itself until two baseband signals are generated. 8. The gain adjustment unit according to claim 1, wherein when the reception level of the first baseband signal is VI, the gain adjustment unit calculates the reception signal strength as (2 × VI ² ) ^1/2 . The portable wireless communication device according to one.

Images