JP2001069107A - Reception controller - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a reception controller for reducing power consumption by optimally controlling reception time. SOLUTION: On the basis of received data, frame synchronizing timing is detected by a frame synchronism detecting circuit 10 and on the basis of the frame synchronizing timing detected by the frame synchronism detecting circuit 10 and a reception control signal, a reception timing error is detected by a frame correcting and detecting circuit 12. On the basis of the reception timing error detected by the frame correcting and detecting circuit 12, the reception timing signal of the next frame to be generated by a reception control timer 11 on the basis of the frame synchronizing timing detected by the frame synchronism detecting circuit 10 is corrected and on the basis of this corrected reception timing signal, the reception control signal is generated by a reception control circuit 13.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a reception control device for a communication device that performs intermittent data communication using a wired line or a wireless line, and in particular, reduces power consumption by optimally controlling a reception time. And a receiving control device.

[0002]

2. Description of the Related Art Generally, a mobile communication terminal such as a portable radio telephone using a TDMA (Time Division Multiplexing) system is configured to intermittently perform data communication in frame units. In order to accurately perform the reception, the frame synchronization is established, and the reception control of the next frame is measured based on the frame synchronization timing to perform the reception control.

[0003] The reception timing of the next frame is measured using a clock on the transmitting side and a system clock in a mobile communication terminal that is asynchronous with the clock. For this reason, a difference may occur between the data transmission timing on the transmission side and the data reception timing on the reception side.

That is, when the reception interval is short, such as during a call, the error in the data reception timing is unlikely to occur, and it is unlikely to affect the reception timing of the next frame, but the battery consumption is minimized. At the time of standby for intermittent reception in order to suppress the delay, the shift in data reception timing becomes large, and the reception of the next frame may not be performed correctly.

[0005] Further, with the rapid spread of mobile communication terminals in recent years, the mobile communication terminals are required to have more functions, but on the other hand, it is necessary to satisfy the demands of cost reduction, low power consumption, and the like. In order to measure the reception timing of the next frame, techniques such as using a low-precision low-speed battery-saving clock have been adopted.
In particular, during standby or the like, a large difference occurs between the data transmission timing on the transmission side and the data reception timing on the reception side.

As a method for solving this problem, a method has conventionally been adopted in which the receiving side is provided with a margin by the difference width in consideration of the difference in clock accuracy between the transmitting side and the receiving side. I have.

[0007] Usually, the number of installed base stations on the transmitting side is smaller than that of mobile communication terminals, and performance corresponding to data transmission timing is required. Therefore, an expensive oscillator with high clock accuracy is used. On the other hand, as described above, the mobile communication terminal uses an oscillator with a low clock accuracy and a very low accuracy having a characteristic that the accuracy changes with temperature and voltage, as described above.

For this reason, the mobile communication terminal on the receiving side needs to set the reception timing of the next frame in consideration of these errors. Specifically, measures are taken to prevent a data reception error from occurring by, for example, lengthening the reception section.

FIG. 6 is a block diagram showing an example of the configuration of a reception control device in a conventional mobile communication terminal. In FIG. 6, a reception control device in a conventional mobile communication terminal includes:
It comprises a frame synchronization detection circuit 10, a reception control timer 11, and a reception control circuit 13.

The frame synchronization detection circuit 10 receives the data received via a radio line (not shown) and the received and reproduced data reproduced from the received data while the reception control signal output from the reception control circuit 13 is at a high level. A clock is input, a unique word (UW) included in received data is correlated with a preset unique word, and a synchronization detection timing is detected from a timing at which the correlation value satisfies a preset reference value. A synchronization detection timing signal indicating the detection timing is generated and output.

The reception control timer 11 counts the battery saving clock based on the synchronization detection timing signal generated by the frame synchronization detection circuit 10, and the count value of the battery saving clock is set to a preset timer set time ta. , A reception timing signal indicating the reception timing of the next frame is output.

The reception control circuit 13 includes a reception control timer 11
And generates and outputs a reception control signal for controlling the operations of the wireless device and the frame synchronization detection circuit 10 based on the reception timing signal output from.

FIG. 7 is a timing chart for explaining the operation of the reception control device shown in FIG. 6 when waiting for an incoming call. The reception control device shown in FIG. 6 performs an intermittent reception operation of receiving a broadcast channel periodically transmitted from a base station (not shown) when waiting for an incoming call.

That is, the base station transmits broadcast data using a broadcast channel at a predetermined period T (intermittent reception period T), and the reception control device shown in FIG. The radio is turned on in synchronization with the cycle T, and the broadcast data transmitted on this broadcast channel is received.

In FIG. 7, the received data shown in FIG. 7 (a) indicates the received data of the broadcast data transmitted on the broadcast channel, and the received data includes a ramp bit R, preamble information PR, and a unique word. It has a frame configuration including UW, data area DATA, and cyclic redundancy check code CRC.

When the reception control signal output from the reception control circuit 13 shown in FIG. 6 changes from a low level to a high level as shown in FIG. 7B, a radio (not shown) of the reception control device is turned on. The frame synchronization detection circuit 10 receives the received data and the received reproduction clock.
Note that the reception control signal shown in FIG. 7B changes from the high level to the low level at the timing when the reception data ends.

The frame synchronization detecting circuit 10 correlates a unique word (UW) included in the received data with a preset unique word based on the input received data and the received reproduction clock, and sets a correlation value in advance. The synchronization detection timing signal is output at a timing satisfying the reference value as shown in FIG.

Based on the synchronization detection timing signal, the reception control timer 11 counts the battery saving clock, and when the count value of the battery saving clock reaches a value corresponding to a preset timer set time ta, As shown in FIG. 7D, a reception timing signal indicating the reception timing of the next frame is output.

The reception control circuit 13 changes the reception control signal from a low level to a high level at the timing of the reception timing signal. When the reception control signal output from the reception control circuit 13 changes from a low level to a high level, a radio (not shown) of the reception control device is turned on, and the reception data and the reception reproduction clock are input to the frame synchronization detection circuit 10. Then, the same operation is repeated.

The timer setting time ta described above is set based on the intermittent reception cycle T. The time from the synchronization detection timing signal to the reception timing of the next frame corresponds to the system clock of the transmission side and the reception side. The error tg is set in consideration of the error tg based on the deviation of the accuracy, that is, the error tg in consideration of the worst condition of the system clock on the transmission side and the reception side.

[0021]

As described above, in the conventional reception control device, it is necessary to set the timer set time ta in consideration of an error tg in consideration of the worst condition of the system clocks on the transmission side and the reception side. The error tg becomes longer, and as a result, there is a problem that the reception time of the mobile communication terminal becomes longer and the battery consumption increases. Therefore, an object of the present invention is to provide a reception control device that reduces power consumption by optimally controlling a reception time.

[0022]

In order to achieve the above object, according to the present invention, a transmission / reception frame signal is generated based on reception data received based on a reception control signal, and the transmission / reception frame signal is generated based on the transmission / reception frame signal. Establish frame synchronization,
In the reception control device that receives the data of the next frame,
A frame synchronization detection circuit that detects a frame synchronization timing based on the reception data, a frame correction detection circuit that detects a reception timing error based on the frame synchronization timing detected by the frame synchronization detection circuit and the reception control signal, A reception control timer for outputting a reception timing signal for the next frame based on the frame synchronization timing detected by the frame synchronization detection circuit; and a reception timing for detecting the reception timing signal output from the reception control timer by the frame correction detection circuit. A reception timing signal correction circuit that corrects based on the error;
A reception control circuit that outputs the reception control signal based on the reception timing signal corrected by the reception timing signal correction circuit.

According to a second aspect of the present invention, in the first aspect of the present invention, the frame correction detecting circuit includes an initial value setting means for setting an initial value of the reception timing error. .

According to a third aspect of the present invention, in the first aspect of the present invention, the reception control timer counts a battery saving clock for counting an intermittent reception cycle for battery saving to thereby provide the reception timing signal. Is output.

According to a fourth aspect of the present invention, in the first aspect of the present invention, the frame synchronization detection circuit detects a frame synchronization timing based on detection of a unique word included in the received frame. I do.

According to a fifth aspect of the present invention, in the first aspect, the frame synchronization detection circuit detects a frame synchronization timing based on a common pilot signal included in the received frame. .

[0027]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a block diagram showing an embodiment of a reception control apparatus according to the present invention. FIG. 1 is a block diagram showing an embodiment of the reception control device according to the present invention.

In FIG. 1, the reception control device includes a frame synchronization detection circuit 10, a reception control timer 11, a frame correction detection circuit 12, a reception control circuit 13, and a timing correction circuit 14.

Here, the frame synchronization detecting circuit 10 reproduces the received data received through a radio line (not shown) and the received data during a period when the reception control signal output from the reception control circuit 13 is at a high level. The received reproduction clock is input, a unique word (UW) included in the received data is correlated with a preset unique word, and a synchronization detection timing is detected from a timing at which the correlation value satisfies a preset reference value. , And generates and outputs a synchronization detection timing signal indicating the synchronization detection timing.

The reception control timer 11 counts the battery saving clock based on the synchronization detection timing signal generated by the frame synchronization detection circuit 10, and the count value of the battery saving clock is set to a preset timer set time ta. , A reception timing signal indicating the reception timing of the next frame is output.

The frame correction detection circuit 12 compares the synchronization detection timing signal supplied from the frame synchronization detection circuit 10 with a calculated synchronization detection timing signal obtained from the reception control signal supplied from the reception control circuit 13. Then, the difference is output as a correction value.

The timing correction circuit 14 corrects the reception timing signal supplied from the reception control timer 11 according to the correction value supplied from the frame correction detection circuit 12, and outputs the result.

The reception control circuit 13 generates a reception control signal for controlling the operations of the radio unit, the frame synchronization detection circuit 10, the frame correction detection circuit 12, and the like (not shown) based on the output of the timing correction circuit 14.

FIG. 2 is a timing chart for explaining the operation of the reception control device shown in FIG. 1 when waiting for an incoming call. The reception control device shown in FIG. 1 performs an intermittent reception operation of receiving a broadcast channel periodically transmitted from a base station (not shown) when waiting for an incoming call.

That is, the base station transmits broadcast data using the broadcast channel at a predetermined period T (intermittent reception period T), and the reception control device shown in FIG. The wireless device (not shown) is turned on in synchronization with the cycle T, and the broadcast data transmitted on this broadcast channel is received.

In FIG. 2, the received data shown in FIG. 2 (a) indicates the received data of the broadcast data transmitted on the broadcast channel, and the received data includes a ramp bit R, preamble information PR, and a unique word. It has a frame configuration including UW, data area DATA, and cyclic redundancy check code CRC.

When the reception control signal output from the reception control circuit 13 shown in FIG. 1 changes from a low level to a high level as shown in FIG. 2B, the radio of the reception control device is turned on, and The synchronization data is input to the synchronization detection circuit 10. Note that FIG.
The reception control signal shown in (b) changes from the high level to the low level at the timing when the reception data ends.

The frame synchronization detecting circuit 10 correlates the unique word UW included in the received data with a preset unique word based on the received data and the received reproduction clock, and the correlation value is set in advance. At a timing satisfying the reference value, a synchronization detection timing signal is output as shown in FIG.

Based on the synchronization detection timing signal, the reception control timer 11 counts the battery saving clock, and when the count value of the battery saving clock reaches a value corresponding to a preset timer set time ta, As shown in FIG. 2E, a reception timing signal indicating the reception timing of the next frame is output.

The frame correction detection circuit 12 calculates the synchronization detection timing signal supplied from the frame synchronization detection circuit 10 and the synchronization detection signal calculated from the reception control signal supplied from the reception control circuit 13 as shown in FIG. The difference is compared with the detection timing signal, and the difference is output as a correction value t1.

The timing correction circuit 14 corrects the reception timing signal supplied from the reception control timer 11 in accordance with the correction value t1 supplied from the frame correction detection circuit 12, and outputs the result.

Here, for example, in FIG. 2, if the calculated synchronization detection timing signal exists earlier (left side) than the synchronization detection timing pulse signal, the correction value t1
Is a positive value, and the calculated synchronization detection timing signal is
If it exists at a later time (right side) than the synchronization detection timing pulse signal, it is added as a negative value to the timer set time ta to generate a corrected reception timing signal.

In the example of FIG. 2, since the calculated synchronization detection timing signal exists earlier (left side) than the synchronization detection timing pulse signal upon reception of the first frame, the correction value t1 is added to the timer set time ta. Is done.

The reception control circuit 13 controls the operation of the radio, the frame synchronization detection circuit 10, the frame correction detection circuit 12, and the like based on the corrected reception timing signal output from the timing correction circuit 14 (FIG. 2B). Is generated.

That is, the reception control circuit 13 corrects the correction value t1 output from the timing correction circuit 14 and goes to a high level in synchronization with the corrected reception timing pulse signal, as shown in FIG. Is generated and supplied to the wireless device, the frame synchronization detection circuit 10, and the like. In addition,
This reception control signal goes low in synchronization with the end of the reception data.

Thereafter, the correction value t2 is similarly set in the next frame.
Is detected. In this case, since the calculated synchronization detection timing signal exists later (right side) than the synchronization detection timing pulse signal, the correction value t2 becomes negative, and the timing correction circuit 14 sets the reception timing signal to the previous correction value t1. Is shifted by an amount corresponding to a value obtained by subtracting the correction value t2 from the correction timing signal to generate a corrected reception timing signal.

Based on the corrected reception timing signal supplied from the timing correction circuit 14, the reception control circuit 13 generates a reception control signal for the next frame which goes high in synchronization with the corrected reception timing signal.

That is, in this embodiment, the frame synchronization timing is detected by the frame synchronization detection circuit 10 based on the received data, and the frame synchronization timing is detected based on the frame synchronization timing detected by the frame synchronization detection circuit 10 and the reception control signal. The timing error is detected by the frame correction detection circuit 12. Then, the reception timing signal of the next frame generated by the reception control timer 11 based on the frame synchronization timing detected by the frame synchronization detection circuit 10 is corrected based on the reception timing error detected by the frame correction detection circuit 12, and this correction is performed. The reception control circuit 13 generates a reception control signal based on the received reception timing signal.

As described above, the deviation of the reception timing on the reception side due to the deviation of the clock accuracy between the transmission side and the reception side is corrected for each frame. It is possible to set tg to a theoretically minimum value. As a result, the reception time of the mobile communication terminal can be controlled to a minimum, so that battery consumption can be reduced.

Even if the received data cannot be received due to the deterioration of the line quality that occurs in this type of mobile communication, if the accumulated correction value measured so far is applied to the reception timing of the next frame, the same applies. An error tg, which is a deviation width of the reception control signal from the reception data, can be reduced.

FIG. 3 is a timing chart for explaining another operation of the reception control apparatus shown in FIG. 1 when waiting for an incoming call. In this type of reception control device, at the stage immediately after the establishment of frame synchronization, it is impossible to detect a difference in clock accuracy between the transmission side and the reception side. Therefore, in FIG. 3, the worst value of the reception timing shift on the receiving side caused by the difference in clock accuracy between the transmitting side and the receiving side immediately after the establishment of frame synchronization is calculated, and this value is used as the initial value ti of the correction value. Set.

That is, the frame correction detection circuit 12
Immediately after frame synchronization is established, the initial value ti of the correction value
The timing correction circuit 14 corrects the reception timing signal output from the reception control timer 11 using the initial value ti of the correction value. As a result, immediately after the frame synchronization is established, the reception control signal becomes high level earlier than the timer set time ta by the initial value ti of the correction value.

After the processing using the initial value ti of the correction value immediately after the establishment of the frame synchronization, the correction value due to the difference in clock accuracy between the transmitting side and the receiving side, that is,
Since the correction value t1 is obtained in FIG. 3, the reception timing is controlled in the same manner as described with reference to FIGS.

That is, immediately after the frame synchronization is established, the reception timing signal output from the reception control timer 11 is corrected using the initial value ti of the correction value, and thereafter, the synchronization detection timing signal and the calculated synchronization timing signal are compared. Difference t
The reception timing signal output from the reception control timer 11 is corrected using 1, t2, and t3.

FIG. 4 is a block diagram showing another embodiment of the reception control device according to the present invention. The reception control apparatus according to the embodiment shown in FIG.
0, reception control timer 11, frame correction detection circuit 12,
The reception control circuit 13 and the microprocessor unit (MP
U) 15.

In the reception control apparatus of this embodiment, a correction value is supplied from the frame correction detection circuit 12 to the microprocessor unit 15, and the microprocessor unit 15 compares the correction value supplied from the frame correction detection circuit 12 with the correction value. , And calculates a set time ta from the synchronization detection timing point calculated from the intermittent reception cycle T to the start of reception of the next frame, and sets the corrected timer set value tb in the reception control timer 11.

The operations of the frame synchronization detection circuit 10, the reception control timer 11, the frame correction detection circuit 12, and the reception control circuit 13 are the same as those in FIG. With such a configuration, the same control as in FIG. 1 can be performed.

The mobile communication terminal such as a portable telephone using the TDMA (time division multiplex) method has been described above.
The present invention can also be applied to a mobile communication terminal such as a mobile phone using a CDMA (code division multiplex) system for performing control.

FIG. 5 is a timing chart for explaining the operation of another embodiment in which the reception control device according to the present invention is applied to a wideband CDMA portable radio telephone.

The portable radio telephone of this embodiment also performs an intermittent reception operation of receiving a broadcast channel periodically transmitted from a base station (not shown) when waiting for an incoming call.

That is, the base station transmits broadcast data using the broadcast channel at a predetermined period T (intermittent reception period T), and the portable radio telephone synchronizes with the intermittent reception period T when waiting for an incoming call. Then, a radio device (not shown) is turned on to receive broadcast data transmitted on this broadcast channel.

In FIG. 5, the received data shown in FIG. 5 (a) indicates the received data of the broadcast data transmitted on the broadcast channel, and the received data includes a search code SC, transport channel data TCD, It has a frame configuration including a common pilot CP.

As a configuration of the reception control device of the portable radio telephone, a configuration similar to the configuration shown in FIG. 1 can be adopted. However, in the portable radio telephone of this embodiment, as described above, the search code SC and the transport channel data T
Since the reception data having the frame configuration including the CD and the common pilot CP is configured to be received on the periodic broadcast channel, the frame synchronization detection circuit 10 is configured to perform frame synchronization based on the common pilot CP. ing.

The operation of this embodiment will be described below with reference to FIGS. Reception control circuit 1 shown in FIG.
When the reception control signal output from the receiver 3 goes from a low level to a high level as shown in FIG. 5 (b), the radio of the reception control device is turned on, and the frame synchronization detection circuit 10 receives the reception data and the reception data. A reproduction clock is input.
The reception control signal shown in FIG. 5B changes from the high level to the low level at the timing when the reception data ends.

The frame synchronization detecting circuit 10 correlates the common pilot CP included in the received data with a preset common pilot based on the received data and the received reproduction clock, and the correlation value is set in advance. The synchronization detection timing signal is output at a timing satisfying the reference value as shown in FIG.

Based on the synchronization detection timing signal, the reception control timer 11 counts the battery saving clock, and when the count value of the battery saving clock reaches a value corresponding to a preset timer set time ta, As shown in FIG. 5E, a reception timing signal indicating the reception timing of the next frame is output.

The frame correction detection circuit 12 calculates the synchronization detection timing signal supplied from the frame synchronization detection circuit 10 and the computational synchronization shown in FIG. 5D obtained from the reception control signal supplied from the reception control circuit 13. The difference is compared with the detection timing signal, and the difference is output as the initial value ti of the correction value.

The timing correction circuit 14 corrects the reception timing signal supplied from the reception control timer 11 according to the initial value ti of the correction value supplied from the frame correction detection circuit 12, and outputs the result.

That is, the frame correction detection circuit 12
Immediately after frame synchronization is established, the initial value ti of the correction value
The timing correction circuit 14 corrects the reception timing signal output from the reception control timer 11 using the initial value ti of the correction value. As a result, immediately after the frame synchronization is established, the reception control signal becomes high level earlier than the timer set time ta by the initial value ti of the correction value.

After the processing using the initial value ti of the correction value immediately after the establishment of the frame synchronization, the correction value due to the difference in clock accuracy between the transmitting side and the receiving side, that is,
Since the correction value t1 is obtained in FIG. 5, the reception timing is controlled in the same manner as described with reference to FIGS. 1 and 2 using the correction value from the reception of the next frame.

That is, immediately after the frame synchronization is established, the reception timing signal output from the reception control timer 11 is corrected using the initial value ti of the correction value, and thereafter, the synchronization detection timing signal and the calculated synchronization timing signal are Difference t
The reception timing signal output from the reception control timer 11 is corrected using 1, t2, and t3.

[0072]

As described above, according to the present invention, a difference in reception timing on the receiving side due to a difference in clock accuracy between the transmitting side and the receiving side is corrected for each frame. It is possible to set the error, which is the deviation width of the signal with respect to the received data, to a theoretically minimum value. As a result, the reception time required for the mobile communication terminal to wait for the incoming call can be controlled to a minimum. Consumption can be reduced.

Even if the received data cannot be received due to the deterioration of the line quality that occurs in this type of mobile communication, if the accumulated correction value measured so far is applied to the reception timing of the next frame, the same applies. It is possible to reduce an error that is a deviation width of the reception control signal from the reception data.

[Brief description of the drawings]

FIG. 1 is a block diagram showing an embodiment of a reception control device according to the present invention.

FIG. 2 is a timing chart for explaining an operation of the reception control device shown in FIG. 1 when waiting for an incoming call;

FIG. 3 is a timing chart for explaining another operation of the reception control device shown in FIG. 1 when waiting for an incoming call;

FIG. 4 is a block diagram showing another embodiment of the reception control device according to the present invention.

FIG. 5 is a timing chart for explaining an operation of another embodiment in which the reception control device according to the present invention is applied to a wideband CDMA portable radio telephone.

FIG. 6 is a block diagram showing a configuration example of a reception control device in a conventional mobile communication terminal.

FIG. 7 is a timing chart for explaining the operation of the reception control device shown in FIG. 6 when waiting for an incoming call;

[Explanation of symbols]

 Reference Signs List 10 frame synchronization detection circuit 11 reception control timer 12 frame correction detection circuit 13 reception control circuit 14 timing correction circuit 15 microprocessor unit (MPU)

Claims (5)

[Claims] 1. A reception control apparatus for generating a transmission / reception frame signal based on reception data received based on a reception control signal, establishing frame synchronization based on the transmission / reception frame, and receiving data of a next frame. A frame synchronization detection circuit that detects a frame synchronization timing based on received data; a frame correction detection circuit that detects a reception timing error based on the frame synchronization timing detected by the frame synchronization detection circuit and the reception control signal; A reception control timer for outputting a reception timing signal of the next frame based on the frame synchronization timing detected by the synchronization detection circuit; and a reception timing error detected by the frame correction detection circuit for the reception timing signal output from the reception control timer. Receiver to correct based on Timing signal correction circuit and the reception control device characterized by comprising a reception control circuit for outputting the received control signal based on the corrected reception timing signal by the reception timing signal correcting circuit. 2. The reception control device according to claim 1, wherein the frame correction detection circuit includes an initial value setting unit that sets an initial value of the reception timing error. 3. The reception control timer according to claim 1, wherein the reception control timer outputs the reception timing signal by counting a battery saving clock for counting an intermittent reception cycle for battery saving.
The reception control device according to any one of the preceding claims. 4. The reception control device according to claim 1, wherein the frame synchronization detection circuit detects a frame synchronization timing based on detection of a unique word included in the received frame. 5. The reception control device according to claim 1, wherein the frame synchronization detection circuit detects a frame synchronization timing based on a common pilot signal included in the received frame.