JP2005260670A - Portable information communication terminal - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To shorten a starting time at the time of receiving operation start when a receiving operation is intermittent for each intermittent receiving period. <P>SOLUTION: Before finishing the receiving operation, an AGC (automatic gain control) circuit starting timing calculating part 130 utilizes one piece or more of speed information and path assignment information and calculates AGC circuit starting timing corresponding to an allowed value of a frequency error to a target frequency in a TCXO (temperature compensated crystal oscillator) 110, and in addition, a receiving level correction coefficient initial value calculating part 131 uses receiving level information of a received signal and frequency error information to the target information of the TCXO 110 and calculates a receiving level correction coefficient initial value. At the time of a receiving operation start, an AGC control part 124 starts an AGC circuit 103 at the AGC circuit starting timing calculated at the time of the previous receiving operation and uses the receiving level correction coefficient initial value calculated at the time of the previous receiving operation to correct the receiving level of the received signal inputted to the AGC circuit 103. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a portable information communication terminal that intermittently receives a reception signal from a base station every intermittent reception period.

  Conventionally, in a portable information communication terminal, there are a reception period, an idle period, and a transmission period as a period for performing signal communication with a base station. Among these, the reception period and the transmission period partially overlap, and in the overlap period, the transmission signal is transmitted to the base station along with the reception of the reception signal from the base station.

  In this type of portable information communication terminal, when it enters a standby state, it does not receive the reception signals from the base station sequentially during all reception periods, but sequentially receives the reception signals from the base station only during a desired reception period. The operation is repeated. In other words, if reception is performed in a certain reception period, the reception signal from the base station is received when the next desired reception period is reached without receiving the signal from the base station until the next desired reception period. A receiving operation is performed.

In such a portable information communication terminal that performs reception operation intermittently, the operation of a means for generating a high-speed clock such as a TCXO (temperature compensated crystal oscillator) is stopped during a non-reception operation in which a reception signal from the base station is not received. However, the power consumption is reduced by generating only the low-speed clock (see, for example, Patent Documents 1 and 2). For this reason, the timing at which the reception operation of the reception signal from the base station is performed next, that is, the period for performing the reception operation (hereinafter referred to as intermittent reception period) is calculated based on the count result of the low-speed clock.
JP 2000-244351 A JP 2000-36770 A

  However, in portable information communication terminals that perform intermittent reception operations, the TCXO is restarted at each intermittent reception cycle, and the AGC circuit that amplifies the reception level of the received signal is restarted after the TCXO operation is stabilized. After the operation of the AGC circuit is stabilized, the reception process is finally started. Therefore, the TCXO and AGC circuits are activated every intermittent reception period, and it takes a long time until the operation is stabilized, so that the activation time is increased, thereby increasing the current consumption. is there.

  Accordingly, an object of the present invention is to provide a portable information communication terminal capable of shortening a startup time at the start of a reception operation and suppressing an increase in current consumption when a reception operation is performed every intermittent reception cycle. .

  When the mobile information communication terminal according to the first aspect of the present invention performs a reception operation intermittently every intermittent reception cycle, the speed information on the moving speed of the mobile information communication terminal or the mobile information communication terminal before the reception operation ends. AGC circuit that uses one or more of the path assignment information related to the path to reach the AGC circuit and is the timing for starting the AGC circuit after the start of the TCXO during the next reception operation, and corresponds to the allowable value of the frequency error with respect to the target frequency in the TCXO An AGC circuit activation timing calculation unit that calculates an activation timing, and a frequency error in the TCXO after the activation of the TCXO at the start of a reception operation, and an AGC circuit activation timing calculated by the AGC circuit activation timing calculation unit during the previous reception operation It has a feature in that it has an AGC control unit that activates the AGC circuit at the time of matching.

  According to this configuration, the start operation of the AGC circuit can be performed when the frequency error of the TCXO reaches the allowable value based on the speed information or the path assignment information without waiting for the TCXO to stabilize at the start of the reception operation. This makes it possible to shorten the startup time.

  And a reception level correction coefficient initial value calculation unit for calculating a reception level correction coefficient initial value by using reception level information of the received signal and frequency error information in the TCXO before the reception operation ends, and AGC control The unit corrects the reception level of the reception signal input to the AGC circuit using the reception level correction coefficient initial value calculated during the previous reception operation by the reception level correction coefficient initial value calculation unit at the start of the reception operation, The corrected received signal may be re-input to the AGC circuit.

  According to this configuration, the reception level of the reception signal input to the AGC circuit can be corrected using the reception level correction coefficient initial value based on the reception level information and the frequency error information in the TCXO at the start of the reception operation. Therefore, the AGC circuit can be started up and stabilized without waiting for the TCXO to stabilize, thereby further shortening the startup time.

  When the portable information communication terminal according to the second aspect of the present invention performs a reception operation intermittently every intermittent reception period, the reception level information and TCXO of the reception signal measured by the reception level measurement unit before the reception operation ends. A reception level correction coefficient initial value calculation unit for calculating a reception level correction coefficient initial value using frequency error information with respect to a target frequency at, and an arbitrary value based on a frequency error in TCXO after starting TCXO at the start of reception operation The AGC circuit is started at the timing, and the reception level of the reception signal input to the AGC circuit is corrected using the reception level correction coefficient initial value calculated by the reception level correction coefficient initial value calculation unit during the previous reception operation. And an AGC control unit that re-inputs the corrected received signal to the AGC circuit.

  According to this configuration, the reception level of the reception signal input to the AGC circuit can be corrected using the reception level correction coefficient initial value based on the reception level information and the frequency error information in the TCXO at the start of the reception operation. Therefore, the AGC circuit can be activated and stabilized without waiting for the TCXO to stabilize, thereby shortening the activation time.

  In addition, before the end of the reception operation, one or more of speed information about the moving speed of the mobile information communication terminal or path assignment information about the path to reach the mobile information communication terminal is used. An AGC circuit activation timing calculating unit that calculates an AGC circuit activation timing corresponding to a frequency error allowable value with respect to a target frequency in the TCXO, the timing at which the circuit is activated. After the TCXO is activated, the AGC circuit may be activated when the frequency error in the TCXO coincides with the AGC circuit activation timing calculated during the previous reception operation by the AGC circuit activation timing calculation unit.

  According to this configuration, when the communication status (movement status or path status) of the portable information communication terminal is such that the AGC circuit can be activated early without waiting for the TCXO to stabilize, the frequency error of the TCXO Since the AGC circuit can be activated when it reaches the allowable value based on the speed information or the path assignment information, the activation time can be further shortened.

  As described above, in the present invention, when the reception operation is intermittently performed at each intermittent reception cycle, the start operation of the AGC circuit is performed without waiting for the TCXO to stabilize at the start of the reception operation, or the AGC is performed. Since the start-up operation and the stabilization operation of the circuit can be performed, the effect of shortening the start-up time and suppressing the increase in current consumption can be obtained.

  The best mode for carrying out the present invention will be described below with reference to the drawings.

  Referring to FIG. 1, the mobile information communication terminal according to the present embodiment intermittently receives a received signal using a high-speed clock for each intermittent reception cycle, and sets the intermittent reception cycle using a low-speed clock during a non-reception operation. It is a terminal to generate. This portable information communication terminal includes an antenna 101, an RF unit 102, an AGC circuit 103, an AFC circuit 104, a modem circuit 105, a baseband processing circuit 106, a speed information acquisition unit 107, and a path assignment information acquisition unit. 108, control unit 109, TCXO 110, low-speed clock circuit 111, PLL circuit 112, switch 113, error counter 114, codec circuit 115, A / D conversion unit 116, recording unit 117, display 118, a microphone 119, a speaker 120, an operation unit 121, a temperature sensor 122, and a battery 123. In FIG. 1, a portion surrounded by a dotted line constitutes a signal processing unit 100.

  The RF unit 102 is connected to the antenna 101 and receives a reception signal from the base station via the antenna 101. The AGC circuit 103 controls the gain of the reception level of the reception signal received by the RF unit 102. The AFC circuit 104 is a circuit for controlling the frequency of the received signal whose gain is controlled by the AGC circuit 103, and the modulation / demodulation circuit 105 is a reception whose frequency is controlled by the AFC circuit 104. The baseband processing circuit 106 is a circuit corresponding to a reception level measuring unit that performs baseband processing of the reception signal demodulated by the modulation / demodulation circuit 105 and measures the reception level of the reception signal. is there.

  The baseband processing circuit 106 includes a speed information acquisition unit 107 that acquires speed information related to the moving speed of the mobile information communication terminal, and path assignment information (for example, between adjacent paths) that reaches the mobile information communication terminal. A path assignment information acquisition unit 108 for acquiring (distance) is connected.

  The temperature sensor 122 is a sensor that detects the temperature in the vicinity of the TCXO 110, the battery 123 is a battery that supplies a power supply voltage to each unit in the portable information communication terminal, and the A / D conversion unit 116 is a battery of the battery 123. This circuit converts the temperature in the vicinity of the TCXO 110 detected by the level / temperature sensor 122 into digital data and inputs the digital data to the control unit 109.

  The low-speed clock circuit 111 is a circuit that always generates a low clock. This low-speed clock is used for generating an intermittent reception period in an intermittent reception period generation unit 132 in the intermittent control unit 127 described later during a non-reception operation. The TCXO 110 generates a high-speed clock during a reception operation and is stopped during a non-reception operation. The PLL circuit 112 generates a high-speed clock obtained by multiplying the high-speed clock generated by the TCXO 110 by n after the TCXO 110 is activated during the reception operation, and inputs the high-speed clock to the control unit 109.

  During the non-reception operation, the switch 113 is switched to the low-speed clock circuit 111 side, and the low-speed clock is supplied into the signal processing unit 100. On the other hand, at the time of the reception operation, the switch 113 is switched to the TCXO 110 side, the high speed clock from the PLL circuit 112 is supplied to the control unit 109, and the TCXO 110 is provided to portions other than the control unit 109 in the signal processing unit 100. The high-speed clock from is supplied. Note that switching of the switch 113 is performed by an activation control unit 128 in an intermittent control unit 127 described later.

  The TCXO 110 and the low-speed clock circuit 111 are connected to an error counter 114 that counts the frequency difference between the two.

  The control unit 109 is a CPU that reads a program stored in the recording medium 125 and executes various controls according to the read program. The control unit 109 performs an operation using a high-speed clock from the TCXO 110 and the PLL circuit 112 during a reception operation. However, during the non-reception operation, only the intermittent control unit 127 (to be described later) in the control unit 109 operates using the low-speed clock from the low-speed clock circuit 111, and the portions other than the intermittent control unit 127 in the control unit 109 operate. Stop. The control unit 109 includes an AGC control unit 124, an AFC control unit 125, and a transmission / reception control unit 126.

  The AGC control unit 124 is a part that controls the AGC circuit 103, and the AFC control unit 125 is a part that controls the AFC circuit 104.

  The transmission / reception control unit 126 is a part that controls the reception operation of the reception signal from the base station and the transmission operation of the transmission signal to the base station, and in particular, a part that controls the intermittent reception operation of the reception signal from the base station. As shown, an intermittent control unit 127 is provided.

  The intermittent control unit 127 includes an activation control unit 128, a TCXO set value calculation unit 129, an AGC circuit activation timing calculation unit 130, a reception level correction coefficient initial value calculation unit 131, and an intermittent reception cycle generation unit 132. ing. In FIG. 1, the intermittent control unit 127 includes both the AGC circuit activation timing calculation unit 130 and the reception level correction coefficient initial value calculation unit 131, but the AGC circuit activation timing calculation unit 130 and the reception level are included. Any one or more of the correction coefficient initial value calculation unit 131 may be provided.

  The TCXO set value calculation unit 129 calculates the TCXO set value to be set in the TCXO 110 using the battery level information of the battery 123 and the temperature information in the vicinity of the TCXO 110 detected by the temperature sensor 122 before the reception operation ends. . The TCXO 110 sets the target frequency by determining the battery level of the battery 123 and the temperature in the vicinity of the TCXO 110 based on the TCXO setting value calculated by the TCXO setting value calculation unit 129 at the time of the previous receiving operation at the start of the receiving operation. The operation is performed so that the high-speed clock generated in step 1 converges to the target frequency.

  For example, the TCXO set value calculation unit 129 can calculate the TCXO set value using the following formula 1 or formula 2. In this case, in Equation 1 or Equation 2, battery level information a and temperature information b are input to f1 and f2, respectively, and a TCXO set value is calculated.

  Further, the TCXO set value calculation unit 129 may calculate the TCXO set value using the table described later using the battery level information and the temperature information.

  The AGC circuit activation timing calculation unit 130 uses one or more of the speed information acquired by the speed information acquisition unit 107 and the path assignment information acquired by the path assignment information acquisition unit 108 before ending the reception operation. The AGC circuit activation timing set in the AGC control unit 124 is calculated. The AGC circuit activation timing indicates the timing at which the AGC circuit 103 is activated after the TCXO 110 is activated in the next reception operation, and corresponds to the allowable value of the frequency error with respect to the target frequency in the TCXO 110. In the AGC control unit 124, when the reception operation starts, after the TCXO 110 is started, the frequency error value in the TCXO 110 coincides with the AGC circuit start timing calculated by the AGC circuit start timing calculation unit 130 during the previous reception operation. The AGC circuit 103 is activated.

  For example, the AGC circuit activation timing calculation unit 130 can calculate the AGC circuit activation timing using Equation 1 or Equation 2. In this case, in Expression 1 or Expression 2, the path assignment information is input as a and the speed information is input as f1 and f2, respectively, and the AGC circuit activation timing is calculated.

  Note that the AGC circuit activation timing calculation unit 130 does not need to use all the path assignment information and speed information as described above even when calculating the AGC circuit activation timing using Equation 1 or Equation 2. One or more pieces of information may be used. However, as a matter of course, if a plurality of pieces of information are used, it is considered that the calculation accuracy is improved and the calculated value is closer to the optimum value. However, since there are restrictions on the calculation time and the recording capacity of the memory and the like in mounting, information to be used is selected in consideration of these restrictions and calculation accuracy.

  In addition, the AGC circuit activation timing calculation unit 130 may calculate the AGC circuit activation timing using one or more of the path assignment information and the speed information using a table described later.

  The reception level correction coefficient initial value calculation unit 131 uses the reception level information measured by the baseband processing circuit 106 and the frequency error information output from the TCXO 110 before terminating the reception operation, and sends it to the AGC control unit 124. The reception level correction coefficient initial value to be set is calculated. In the AGC control unit 124, when the reception operation starts, the reception level of the reception signal input to the AGC circuit 103 using the reception level correction coefficient initial value calculated by the reception level correction coefficient initial value calculation unit 131 during the previous reception operation. And the corrected received signal is re-input to the AGC circuit 103.

  For example, the reception level correction coefficient initial value calculation unit 131 can calculate the reception level correction coefficient initial value using Equation 1 or Equation 2. In this case, the reception level correction coefficient initial value is calculated by inputting reception level information a and frequency error information b to f1 and f2 in Expression 1 or Expression 2, respectively.

  The reception level correction coefficient initial value calculation unit 131 calculates not only the reception level information measured by the baseband processing circuit 106 during the previous reception operation but also the previous reception operation when calculating the reception level correction coefficient initial value. Sometimes, the reception level information measured by the baseband processing circuit 106 or the cumulative value of the reception level information measured by the baseband processing circuit 106 until the current reception operation may be used.

For example, the reception level correction coefficient initial value calculation unit 131, when using the cumulative value up to this time as reception level information, assumes that the cumulative value up to the previous time is an _-1 and the current measurement value is a, the forgetting factor. a (0 ≦ a <1: any configurable) employs a moving average formula using to calculate the cumulative value a _n up time by the following equation 3.

  Also, the reception level correction coefficient initial value calculation unit 131 may calculate the reception level correction coefficient initial value using the table described later, using the reception level information and the frequency error information.

  The activation control unit 128, when starting the reception operation, sets the TCXO set value and the AGC circuit activation timing calculated by the TCXO set value calculation unit 129, the AGC circuit activation timing calculation unit 130, and the reception level correction coefficient initial value calculation unit 131, respectively. The reception level correction coefficient initial value is acquired, and activation control of the TCXO 110, the PLL circuit 112, and the AGC control unit 124 is performed using the acquired information. In addition, the activation control unit 128 also performs switching of the switch 113 at the time of shifting to the receiving operation and at the time of shifting to the non-receiving operation.

  The intermittent reception cycle generation unit 132 generates an intermittent reception cycle using the low-speed clock from the low-speed clock circuit 111 during the non-reception operation. For each intermittent reception cycle, the activation control unit 128 starts a reception operation.

  The display 118 is a part for displaying necessary information to the user, the microphone 119 is a part for inputting sound, the speaker 120 is a part for outputting sound, and the codec circuit 115 is a microphone. 119 and a circuit that performs codec processing of audio input / output through the speaker 120, and the operation unit 121 is a part where the user operates the portable information communication terminal.

  The recording unit 117 stores a program executed by the control unit 109 as described above. In addition, information calculated by the TCXO set value calculation unit 129, the AGC circuit activation timing calculation unit 130, and the reception level correction coefficient initial value calculation unit 131 can be stored.

  Hereinafter, the operation of the portable information communication terminal shown in FIG. 1 will be described. Note that the mobile information communication terminal according to the present embodiment performs the same operation as a well-known operation regarding a call operation and a transmission operation. Here, an example of a reception operation that is intermittently performed every intermittent reception cycle is described here. explain.

  During a non-reception operation in which the reception signal from the base station is not received, the switch 113 is switched to the low-speed clock circuit 111 side, and the low-speed clock from the low-speed clock circuit 111 is supplied into the signal processing unit 100. Yes. Further, in the control unit 109, the operation other than the intermittent control unit 127 is stopped, and in the intermittent control unit 127, the intermittent reception cycle generation unit 132 uses the low-speed clock from the low-speed clock circuit 111 to perform intermittent reception. A period is generated. Under such circumstances, in the intermittent control unit 127, the activation control unit 128 starts a reception operation for receiving a reception signal from the base station according to the intermittent reception cycle generated by the intermittent reception cycle generation unit 132. To do.

  Referring to FIG. 2, first, activation control unit 128 starts TCXO set value calculation unit 129, AGC circuit activation timing calculation unit 130, and reception level correction coefficient initial value calculation unit during the previous reception operation when starting a reception operation. The TCXO set value, the AGC circuit activation timing, and the reception level correction coefficient initial value calculated in 131 are acquired (steps 201 to 203).

  Next, the activation control unit 128 sets the TCXO setting value acquired in step 201 to the TCXO 110 and activates the TCXO 110 (step 204), and the AGC circuit activation timing and reception level correction coefficient initial values acquired in steps 202 and 203. The value is set in the AGC control unit 124, and the AGC control unit 124 is activated (step 205).

  Next, the TCXO 110 determines the battery level of the battery 123 and the temperature in the vicinity of the TCXO 110 based on the TCXO set value set by the activation control unit 128, sets the frequency corresponding to the battery level and the temperature to the target frequency, and thereafter The TCXO 110 starts operation so that the high-speed clock generated by the TCXO 110 converges to the target frequency. Further, a frequency error value between the frequency of the currently generated high-speed clock and the target frequency is calculated and output to the activation control unit 128 and the AGC control unit 124 in the intermittent control unit 127 (step 206).

  Here, the activation control unit 128 determines whether or not the PLL circuit 112 can be activated based on the frequency error value output from the TCXO 110 (step 207), and if it is determined that the PLL circuit 112 can be activated, the PLL circuit 112. Is activated (step 208).

  On the other hand, the AGC control unit 124 determines whether the AGC circuit 103 can be activated based on whether the frequency error value output from the TCXO 110 matches the AGC circuit activation timing acquired in step 202 (step 209), when it is determined that the AGC circuit 103 is ready to be activated, the AGC circuit 103 is activated (step 210).

  Since the reception signal input to the AGC circuit 103 immediately after starting the AGC circuit 103 in step 209 is considered to have been input without the TCXO 110 reaching the target frequency, when the TCXO 110 reaches the target frequency There is a level difference from the true reception level. Therefore, the AGC control unit 124 calculates a reception level correction coefficient based on the frequency error value output from the TCXO 110 and the reception level correction coefficient initial value set by the activation control unit 128, and uses the calculated reception level correction coefficient. Then, the reception signal input to the AGC circuit 103 is corrected to a true reception level, and the corrected reception signal is input again to the AGC circuit 103 (step 211). As a result, the AGC circuit 103 can be activated and stabilized without waiting for the frequency generated by the TCXO 110 to reach the target frequency and the output to stabilize.

  After the outputs of the TCXO 110 and the PLL circuit 112 are stabilized (Steps 212 and 213), the activation control unit 128 switches the switch 113 to the TCXO 110 side and supplies the control unit 109 with the high-speed clock from the TCXO 110 and the PLL circuit 112. Further, a high-speed clock from the TCXO 110 is supplied to a portion other than the control unit 109 in the signal processing unit 100 and a portion other than the intermittent control unit 127 in the control unit 109 is activated. Further, after the output of the AGC circuit 103 is stabilized (step 214), reception processing for receiving a reception signal from the base station is performed (step 215). Note that the reception operation after the output of the AGC circuit 103 has been stabilized may be performed using a known technique, and thus the description thereof is omitted here.

  Thereafter, when the reception operation is terminated, the TCXO set value calculation unit 129, the AGC circuit activation timing calculation unit 130, and the reception level correction coefficient initial value calculation unit 131 respectively perform the TCXO set value and the AGC circuit activation at the previous stage. Processing for calculating parameters of timing and reception level correction coefficient initial values is performed (step 216).

  In addition, the activation control unit 128 stops the operation of the control unit 109 other than the intermittent control unit 127, and subsequently stops the operation of the TCXO 110 and the PLL circuit 112, and then switches the switch 113 to the low-speed clock circuit 111. (Step 217).

  Next, an example of parameter calculation processing performed before step 216 illustrated in FIG. 2 ends the reception operation will be described.

  In this portable information communication terminal, it is necessary to operate only with the low-speed clock from the low-speed clock circuit 111 immediately after the start of the reception operation, so that it is difficult to perform complicated calculations. Therefore, before ending the reception operation (when operating with the high-speed clock from the TCXO 110), parameters of the TCXO set value, AGC circuit activation timing, and reception level correction coefficient initial value are calculated and used. At the start of the next reception operation, the TCXO 110 is activated and stabilized, and the AGC circuit 103 is activated and stabilized. Note that in step 216 shown in FIG. 2, when calculating the parameters, as described above, it is also possible to calculate using the above formula 1 or 2, but here, the recording unit 117 or the like A case where parameters are calculated using a table stored in will be described as an example.

  Referring to FIG. 3, the TCXO set value calculation unit 129 acquires the battery level information of the battery 123 and the temperature information in the vicinity of the TCXO 110 detected by the temperature sensor 122 as digital data via the A / D conversion unit 116. (Steps 301 and 302). Then, using the battery level information and the temperature level information, a TCXO set value to be set in the TCXO 110 is calculated using a table (step 303).

  For example, the TCXO set value calculation unit 129 uses a two-dimensional table as shown in Table 1 below (the battery level is c and the temperature level is d), and corresponds to the battery level and temperature level values c and d. Let value e be the TCXO set value. When the battery level and temperature level values are intermediate values, the TCXO set value may be obtained after interpolation calculation of such intermediate values.

  Alternatively, the TCXO set value calculation unit 129 determines a value C corresponding to the battery level value c by using a one-dimensional table (battery level is set to c) as shown in Table 2 below, and Table 3 below. Is used to determine a value D corresponding to the temperature level value d, and e00 indicating the C, D and the base value of the TCXO set value. The value e calculated by the following equation 4 is used as the TCXO set value.

  The AGC circuit activation timing calculation unit 130 acquires the speed information acquired by the speed information acquisition unit 107 and the path assignment information acquired by the path assignment information acquisition unit 108 (steps 304 and 305). Then, using any one or more of the speed information and the path assignment information, the AGC circuit activation timing set in the AGC control unit 124 is calculated using the table (step 306).

  For example, when the AGC circuit activation timing calculation unit 130 calculates the AGC circuit activation timing using both the speed information and the path assignment information, the two-dimensional table (the speed level is c and the path assignment level is set as shown in Table 1 above). A value e corresponding to the speed level and path assignment level values c and d is used as the AGC circuit activation timing. If the values of the speed level and the pass assignment level are intermediate values, the TCXO set value may be obtained after performing interpolation calculation of such intermediate values.

  Alternatively, the AGC circuit activation timing calculation unit 130 determines a value C corresponding to the speed level value c using a one-dimensional table as shown in Table 2 (the speed level is c), and 3 is used to determine a value D corresponding to the value d of the path assignment level using a one-dimensional table (having a path assignment level of d) as shown in FIG. Using e00 indicating the value, the value e calculated by Equation 4 is used as the AGC circuit activation timing.

  The reception level correction coefficient initial value calculation unit 131 acquires the reception level information measured by the baseband processing circuit 106 and the frequency error information output from the TCXO 110 (steps 307 and 308). Then, using the reception level information and frequency error information, a reception level correction coefficient initial value is calculated using a table (step 309).

  For example, the reception level correction coefficient initial value calculation unit 131 uses a two-dimensional table (the reception level is c and the frequency error level is d) as shown in Table 1 above, and the reception level and frequency error level values c are used. , D is a reception level correction coefficient initial value. If the values of the reception level and the frequency error level are intermediate values, the initial value of the reception level correction coefficient may be obtained after interpolation calculation of such intermediate values.

  Alternatively, the reception level correction coefficient initial value calculation unit 131 determines a value C corresponding to the reception level value c by using a one-dimensional table (the reception level is c) as shown in Table 2 above. A value D corresponding to the frequency error level value d is determined using a one-dimensional table (having a frequency error level of d) as shown in Table 3 above, and the C, D and reception level correction coefficient are determined. Using e00 indicating the base value of the initial value, the value e calculated by Equation 4 is used as the reception level correction coefficient initial value.

  Thereafter, the activation control unit 128 stores the TCXO set value, the AGC circuit activation timing, and the reception level correction coefficient initial value calculated in steps 301 to 309 in a memory (not shown) in the recording unit 125 or the intermittent control unit 127. (Step 310).

  The values in each table are set to arbitrary values so that the TCXO setting value, the AGC circuit start timing setting value, and the reception level correction coefficient initial value become desired values within a physically settable range. Is possible. However, with respect to the values of the table used for calculating the AGC circuit activation timing, there are two or more paths that reach the portable information communication terminal and these paths are close in time, or the portable information communication When the moving speed of the terminal is fast, it is preferable to set the AGC circuit activation timing to be delayed.

  As described above, in the present embodiment, when the reception operation is intermittently performed at each intermittent reception cycle, the TCXO set value, the AGC circuit activation timing, the reception level correction coefficient calculated at the time of the previous reception operation at the start of the reception operation Since the initial value is used to start up and stabilize the TCXO 110 and start up and stabilize the AGC circuit 103, the startup time can be shortened.

  In addition, the AGC circuit activation timing calculation unit 130 uses one or more of the speed information and the path assignment information before the reception operation is completed, and an AGC circuit corresponding to the allowable value of the frequency error with respect to the target frequency in the TCXO 110 The start timing is calculated, and the AGC control unit 124 starts the AGC circuit 103 at the timing calculated at the time of the previous reception operation when the reception operation is started. Therefore, the AGC control unit 124 waits for the output of the TCXO 110 to stabilize after the TCXO 110 is started. Even if the output of the TCXO 110 reaches the allowable value, the start-up operation of the AGC circuit 103 can be performed, thereby further shortening the start-up time.

  In addition, the reception level correction coefficient initial value calculation unit 131 calculates the reception level correction coefficient initial value using the reception level information and the frequency error information with respect to the target frequency in the TCXO 110 before the reception operation ends, and performs AGC control. Since the reception level of the reception signal input to the AGC circuit 103 is corrected using the initial value of the reception level correction coefficient calculated during the previous reception operation at the start of the reception operation in the unit 124, after the TCXO 110 is started The operation of stabilizing the output of the AGC circuit 103 can be performed without waiting for the output of the TCXO 110 to be stabilized, thereby further shortening the startup time.

  Therefore, in this embodiment, in order to further shorten the activation time at the start of the reception operation, it is necessary to include both the AGC circuit activation timing calculation unit 130 and the reception level correction coefficient initial value calculation unit 131. It is sufficient to provide at least one of them.

  That is, even when only the AGC circuit activation timing calculation unit 130 is provided and the reception level correction coefficient initial value calculation unit 131 is not provided, the output of the TCXO 110 is not transmitted until the output of the TCXO 110 is stabilized. Since the starting operation of the AGC circuit 103 can be performed when the allowable value based on the path assignment information is reached, the starting time can be shortened. However, in this configuration, since it is not intended to stabilize the output of the AGC circuit 103, it is considered that the time until the output of the AGC circuit 103 is stabilized increases. Therefore, in order to shorten the time until the output of the AGC circuit 103 is stabilized, a reception level correction coefficient initial value calculation unit 131 is provided, and the AGC control unit 124 uses the reception level correction coefficient initial value as described above. It is preferable to perform the same operation.

  Conversely, even when only the reception level correction coefficient initial value calculation unit 131 is provided and the AGC circuit activation timing calculation unit 130 is not provided, the output of the AGC circuit 103 is not waited for the output of the TCXO 110 to be stabilized. Since it can be stabilized, the start-up time can be shortened. In this configuration, the AGC control unit 124 activates the AGC circuit 103 at an arbitrary timing based on the frequency error in the TCXO 110. However, depending on the communication status (movement status or path status) of the portable information communication terminal, it may be considered that the AGC circuit 103 may be activated when the output of the TCXO 110 reaches an allowable value. However, with this configuration, even in such a case, the AGC circuit 103 cannot be activated early. Therefore, when the AGC circuit 103 can be activated early, in order to shorten the activation time of the AGC circuit 103, an AGC circuit activation timing calculation unit 130 is provided, and the AGC control unit 124 sets the AGC circuit activation timing. It is preferable to perform the same operation as described above.

  In the present embodiment, before the reception operation ends, the TCXO set value, the AGC circuit activation timing, and the reception level correction coefficient initial value are calculated using the high-speed clock from the TCXO 110 and the PLL circuit 112. However, the TCXO set value, the AGC circuit activation timing, and the reception level correction coefficient initial value only have to be calculated by the time when the next reception operation is started, and when it is necessary to operate only with the low-speed clock, It is possible to perform calculations to the extent that a table is used. For this reason, in the present embodiment, the TCXO set value, the AGC circuit activation timing, and the reception level correction coefficient initial value may be calculated using the low-speed clock from the low-speed clock circuit 5 during the non-reception operation.

  In the present embodiment, the frequency error information of the TCXO 110 is transmitted in pulses as UP / DOWN information indicating the magnitude of the frequency error when the AGC control unit 124 starts the operation of correcting the reception level of the received signal. Anyway. According to this configuration, when the frequency error information itself is transmitted, bus connection for several bits is necessary, but only the wiring for pulse transmission is necessary, so the number of wirings is reduced. be able to.

  In the present embodiment, the AGC control unit 124 may calculate the reception level correction coefficient based only on the reception level correction coefficient initial value. According to this configuration, it is possible to reduce wiring for transmitting frequency error information from the TCXO 110 to the AGC control unit 124.

  In the present embodiment, the calculation results of the TCXO set value, the AGC circuit activation timing, and the reception level correction coefficient initial value are stored for a plurality of times, and it is determined that the reception state of the portable information communication terminal is substantially the same. For example, the previous calculation result may be used as it is without calculating the TCXO set value, the AGC circuit activation timing, and the reception level correction coefficient initial value. According to this configuration, it is also possible to reduce power consumption related to computation.

  In the present embodiment, when it is determined that the reception state of the portable information communication terminal is substantially the same (for example, when the mobile information communication terminal is stationary), the setting values of the TCXO 110 and the AGC circuit 103 are finally the same. Therefore, it is possible to speed up the startup by setting the startup timing of the TCXO 110 and the AGC circuit 103 earlier in stages.

  In the present embodiment, when the mobile information communication terminal fails to start, the setting may be returned to the initial state and then readjustment may be performed. According to this configuration, it is possible to cope with a sudden change in the reception state from the previous reception operation.

It is a block diagram which shows the structure of the portable information communication terminal by one Embodiment of this invention. 3 is a flowchart for explaining a reception operation of the portable information communication terminal shown in FIG. It is a flowchart explaining the parameter calculation process of step 216 shown in FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 100 Signal processing part 101 Antenna 102 RF unit 103 AGC circuit 104 AFC circuit 105 Modulation / demodulation circuit 106 Baseband processing circuit 107 Speed information acquisition part 108 Path assignment information acquisition part 109 Control part 110 TCXO
DESCRIPTION OF SYMBOLS 111 Low speed clock circuit 112 PLL circuit 113 Switch 114 Error counter 115 Codec circuit 116 A / D converter 117 Recording part 118 Display 119 Microphone 120 Speaker 121 Operation part 122 Temperature sensor 123 Battery 124 AGC control part 125 AGC circuit 126 Transmission / reception control part 127 Intermittent control unit 128 Activation control unit 129 TCXO set value calculation unit 130 AGC circuit activation timing calculation unit 131 Reception level correction coefficient initial value calculation unit 132 Intermittent reception cycle generation unit

Claims (5)

In a portable information communication terminal that performs reception operation of a reception signal intermittently using a high-speed clock for each intermittent reception cycle, and generates the intermittent reception cycle using a low-speed clock during non-reception operation,
A low-speed clock circuit that constantly generates the low-speed clock; and
A TCXO that generates the high-speed clock during a reception operation and is stopped during a non-reception operation;
An AGC circuit for controlling a gain of a reception level of the reception signal;
A speed information acquisition unit that acquires speed information related to a moving speed of the portable information communication terminal;
A path assignment information acquisition unit for acquiring path assignment information related to a path reaching the portable information communication terminal;
Prior to the end of the reception operation, one or more of the speed information acquired by the speed information acquisition unit or the path assignment information acquired by the path assignment information acquisition unit is used. An AGC circuit activation timing calculation unit for calculating an AGC circuit activation timing corresponding to an allowable value of a frequency error with respect to a target frequency in the TCXO, which is a timing at which the AGC circuit is activated;
When the reception operation starts, after the TCXO is activated, the AGC circuit is activated when the frequency error in the TCXO coincides with the AGC circuit activation timing calculated during the previous reception operation by the AGC circuit activation timing calculation unit. A portable information communication terminal having an AGC control unit to be activated. A reception level measurement unit for measuring a reception level of the reception signal;
Receiving level correction coefficient initial value calculation that uses the reception level information of the received signal measured by the reception level measuring unit and the frequency error information in the TCXO to calculate the initial value of the reception level correction coefficient before the reception operation ends. And further comprising
The AGC control unit receives the reception signal input to the AGC circuit using the reception level correction coefficient initial value calculated by the reception level correction coefficient initial value calculation unit during the previous reception operation by the reception level correction coefficient initial value calculation unit. The portable information communication terminal according to claim 1, wherein the portable information communication terminal corrects the level and re-inputs the corrected received signal to the AGC circuit. In a portable information communication terminal that performs reception operation of a reception signal intermittently using a high-speed clock for each intermittent reception cycle, and generates the intermittent reception cycle using a low-speed clock during non-reception operation,
A low-speed clock circuit that constantly generates the low-speed clock; and
A TCXO that generates the high-speed clock during a reception operation and is stopped during a non-reception operation;
An AGC circuit for controlling a gain of a reception level of the reception signal;
A reception level measurement unit for measuring a reception level of the reception signal;
The reception level correction coefficient initial value for calculating the initial value of the reception level correction coefficient is calculated using the reception level information of the reception signal measured by the reception level measurement unit and the frequency error information with respect to the target frequency in the TCXO before the reception operation ends. A value calculator,
The AGC circuit is activated at an arbitrary timing based on the frequency error in the TCXO after the TCXO is activated at the start of the reception operation, and is calculated by the reception level correction coefficient initial value calculation unit during the previous reception operation. A portable information communication terminal comprising: an AGC control unit that corrects a reception level of a reception signal input to the AGC circuit using a reception level correction coefficient initial value and re-inputs the corrected reception signal to the AGC circuit. A speed information acquisition unit that acquires speed information related to a moving speed of the portable information communication terminal;
A path assignment information acquisition unit for acquiring path assignment information related to a path reaching the portable information communication terminal;
Prior to the end of the reception operation, the AGC circuit is activated after activation of the TCXO using one or more of the velocity information acquired by the velocity information acquisition unit or the path assignment information acquired by the path assignment information acquisition unit. An AGC circuit activation timing calculating unit that calculates an AGC circuit activation timing corresponding to an allowable value of the frequency error in the TCXO,
When the AGC control unit starts the reception operation, after the TCXO is activated, the frequency error in the TCXO coincides with the AGC circuit activation timing calculated during the previous reception operation by the AGC circuit activation timing calculation unit The portable information communication terminal according to claim 3, wherein the AGC circuit is activated. A battery for supplying a power supply voltage to the portable information communication terminal;
A temperature sensor for detecting a temperature in the vicinity of the TCXO;
A TCXO set value calculation unit that calculates the TCXO set value of the TCXO using the battery level information of the battery and the temperature information in the vicinity of the TCXO detected by the temperature sensor before the end of the reception operation; ,
The mobile information according to any one of claims 1 to 4, wherein the TCXO sets the target frequency based on a TCXO setting value calculated during a previous receiving operation based on the TCXO setting value at the start of a receiving operation. Communication terminal.

Images