JP2000196579A - Radio communication equipment for digital data and radio communication method for digital data - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prolong a battery service life by confirming a bit synchronizing signal without increasing current consumption in a radio communication equipment for digital data. SOLUTION: Number of edges of radio reception signals for a prescribed time is counted by not oscillating a main clock 27 but oscillating only a sub block 28 to discriminate a bit synchronizing signal with rough accuracy. When a signal is possibly the bit synchronizing signal, the main clock 27 is oscillated to measure an edge interval of the radio reception signal go as to discriminate the bit synchronizing signal with high accuracy. When the signal is not the bit synchronizing signal, the oscillation of the main clock 27 is stopped.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of intermittently receiving a signal transmitted by adding a bit synchronization signal before data to be transmitted, and acquiring the synchronization by the bit synchronization signal every time a receiving operation is performed. And a wireless communication method for digital data.

[0002]

2. Description of the Related Art A configuration in which a bit synchronization signal is added before data to be transmitted and transmitted, intermittent reception is performed on the receiving side, and synchronization is acquired with the bit synchronization signal every time a receiving operation is performed. There is a wireless communication device for digital data. An example of such a wireless communication device is a wireless telemeter. In the wireless communication standard for wireless telemeters, a signal having data to be transmitted is configured as shown in FIG. That is, the header section 30 has "0"
And a bit synchronization signal 31 in which “1” are alternately arranged.
It is composed of a frame synchronization signal 32 of a bit M sequence code and a call signal 33 including a call name and an error correction code. The header section 30 is followed by data 34 to be transmitted. On the receiving side, the header section 30 is picked up and the bit synchronization signal 3
1 to perform synchronization acquisition, synchronize the frame with the frame synchronization signal 32, and look at the call signal 33 to determine whether or not the signal is a signal to be received. To start receiving.

[0003] The synchronization acquisition of the bit synchronization signal 31 will be described. A conventional digital data wireless communication device using a one-chip microcomputer of a two-clock system has a high-frequency high-speed main clock and a lower-speed main clock.
And a sub clock that consumes less current. Then, in order to reduce the current consumption, the operation is normally performed only with a low-speed sub clock, and the processing is performed by oscillating the main clock only when necessary.

Usually, a method of measuring the time of an event using a timer in a one-chip microcomputer of a two-clock system is to operate a counter by a clock of the microcomputer while the event is occurring, and count the number of counts. Measure the time. That is, the number of clocks of the event is measured.

FIG. 8 shows a bit synchronization signal. In a conventional digital data wireless communication apparatus using a one-chip microcomputer of a two-clock system, in order to capture and determine the bit synchronization signal of the header part 30, the interval time between the rising edges 35 and the falling edges 36 Or the interval time between the rising edge 35 and the falling edge 36 (collectively referred to as edge interval time) is measured and determined as described above.

[0006]

However, in this method, when operating with a subclock, the clock is slow, so that high-speed events such as the edge interval time of the bit synchronization signal cannot be measured. The measurement cannot be performed only by the subclock, and therefore, when the operation is performed by the subclock, the bit synchronization signal cannot be confirmed. Therefore, the main clock is oscillated, and the edge interval time of the bit synchronization signal is measured by the count number.

However, when the main clock is oscillated as described above, the current consumption increases as described above. For this reason, there is a problem that the battery life is shortened in a digital data wireless communication device mainly using a battery as a power source.

[0008]

According to a first aspect of the present invention, there is provided a digital data radio communication apparatus.
A radio reception signal transmitted by adding a bit synchronization signal before data to be transmitted is intermittently received, and the bit synchronization signal is acquired for each reception operation, and an edge interval of the radio reception signal is obtained. Only when the time is equal to the corresponding edge interval time of the bit synchronization signal, in the wireless communication device for digital data that performs the interval time determination that determines the wireless reception signal to be the bit synchronization signal, the in-clock and the frequency A counter for counting the number of rising edges or the number of falling edges KG of the radio reception signal during a fixed time TC under the oscillation of the subclock;
If G does not fall within the range R that can occur as the number KB of the corresponding edges in the bit synchronization signal during the time TC, it is determined that the radio reception signal is not the bit synchronization signal, and the number KG is If the radio reception signal falls within the range R, the number of edges is determined to determine that the radio reception signal may be the bit synchronization signal.
When G is within the range R, the main clock is oscillated to determine the interval time. If it is determined that the radio reception signal is not the bit synchronization signal, the main clock oscillation is stopped. And a control unit that performs the control.

With the above configuration, the control unit oscillates the sub clock. The above counter is used for a fixed time TC.
During the period, the number of rising edges or the number of falling edges KG of the radio reception signal is counted. The control unit compares the number KG with the number KB of the corresponding edges of the bit synchronization signal during the time TC, and determines whether the number KG falls within a range R that can occur as KB. Find out what.

If the number KG does not fall within the range R, the control unit determines that the radio reception signal is not the bit synchronization signal. It is determined that the received signal may be the bit synchronization signal. As described above, the number of edges is determined as a rough first investigation.

When the number KG falls within the range R that can occur as KB, the radio reception signal may be the bit synchronization signal, and the control unit may oscillate the main clock. Then, the interval time is determined as a more detailed second investigation. That is, the edge interval time TG of the wireless reception signal is measured. It is checked whether the edge interval time TG is equal to the corresponding edge interval time TB of the bit synchronization signal. If TG is not equal to TB, it is determined that the wireless reception signal is not the bit synchronization signal, and oscillation of the main clock is stopped. On the other hand, if TG is equal to TB, the wireless reception signal is determined to be the bit synchronization signal.

Although the main clock has a higher frequency than the sub clock, it is faster than the sub clock, but the power consumption of the device is greater than that in the case of operating with the sub clock. Therefore, as described above, first, a rough first check is performed using the sub clock, and only when there is a possibility that the radio reception signal is a bit synchronization signal, the main clock is oscillated to perform a strict second check. To Also, if the radio reception signal is not a bit synchronization signal,
Immediately stops the oscillation of the main clock and returns to the operation state by the sub clock.

Therefore, it is not necessary to always oscillate the main clock when checking the bit synchronization signal, and the time during which the main clock rises can be shortened. Therefore, the bit synchronization signal can be confirmed without increasing current consumption, and in particular, the battery life of a digital data wireless communication device mainly powered by a battery can be extended.

According to the second aspect of the present invention, in addition to the configuration of the first aspect, when the interval time is determined not to be a bit synchronization signal as a result of the interval time determination, the predetermined time TC is increased. When the interval time is determined to be a bit synchronization signal as a result of the interval time determination, a time control unit that reduces the predetermined time TC is provided.

According to the above configuration, when it is determined that the signal is not a bit synchronization signal as a result of the interval time determination under main clock oscillation, the time control unit increases the predetermined time TC. Conversely, when it is determined that the signal is a bit synchronization signal as a result of the interval time determination, the time control unit reduces the predetermined time TC.

If TC is increased, the probability that the number KG accidentally falls within the range R that can occur as KB, even though it is not a bit synchronization signal, is reduced. Therefore, it is possible to narrow the range for determining that there is a possibility of being a bit synchronization signal. Conversely, TC
Is small, the probability that the number KG accidentally falls within the range R that can occur as KB increases. Therefore, it is possible to widen the range for determining that there is a possibility that the signal is a bit synchronization signal.

Therefore, even though it is determined that there is a possibility of a bit synchronization signal in the above-mentioned edge number determination as a rough first investigation under subclock oscillation, a finer second investigation under main clock oscillation is performed. If it is determined that the signal is not a bit synchronization signal as a result of the above interval time determination, the predetermined time TC is increased in order to increase the accuracy of the first check under subclock oscillation.

Conversely, when the interval time is determined as the second check, if it is determined that the signal is a bit synchronization signal, it is determined in the first check that there is a possibility of a bit synchronization signal. In other words, it means that the second investigation has a high probability of determining that the signal is a bit synchronization signal.
That is, even if the above-mentioned predetermined time TC is reduced, no trouble is likely to occur. Therefore, the predetermined time TC is reduced. This shortens the time of the first survey,
Power consumption can be reduced accordingly.

Therefore, in addition to the effect of the configuration of claim 1, by changing the determination accuracy of the radio reception signal according to the installed radio wave environment, high accuracy and low power consumption can be achieved.
The bit synchronization signal can be checked efficiently.

According to a third aspect of the present invention, there is provided a wireless communication method for digital data, wherein a bit synchronization signal is added before data to be transmitted, and a wireless reception signal transmitted is intermittently received. A signal is synchronously acquired, and only when the edge interval time of the radio reception signal is equal to the corresponding edge interval time of the bit synchronization signal, is the interval time determination for judging the radio reception signal to be the bit synchronization signal. In the wireless communication method of digital data to be performed, a sub-clock is oscillated, and during a certain time TC,
The number of rising edges or the number of falling edges KG of the radio reception signal is counted, and the number KG is the time TC of the corresponding edge in the bit synchronization signal.
It is checked whether or not the number KG falls within a range R that can occur as the number KB, and if the number KG does not fall within the range R,
It is determined that the radio reception signal is not the bit synchronization signal, and if the number KG falls within the range R, the number of edges is determined to determine that the radio reception signal may be the bit synchronization signal. , The number KG is in the range R
If the radio reception signal is not the bit synchronization signal, the main clock is oscillated, and if the radio reception signal is not the bit synchronization signal, the main clock is oscillated. It is characterized by stopping.

The sub clock is oscillated by the above method. During a fixed time TC, the number K of rising edges or the number K of falling edges of the radio reception signal
Count G. The number KG and the bit synchronization signal,
A comparison is made with the number KB of the corresponding edges during the time TC to determine whether or not the number KG falls within a range that can occur as KB.

If the number KG does not fall within the range R, it is determined that the radio reception signal is not the bit synchronization signal, and if the number KG falls within the range R, the radio reception signal becomes the bit synchronization signal. It is determined that the signal may be a synchronization signal. As described above, the number of edges is determined as a rough first investigation.

If the number KG falls within the range R that can occur as KB, the radio reception signal may be the bit synchronization signal, and the main clock is oscillated. As a second survey, the above-described interval time determination is performed. That is, the edge interval time TG of the wireless reception signal is measured. It is checked whether the edge interval time TG is equal to the corresponding edge interval time TB of the bit synchronization signal. If TG is not equal to TB, it is determined that the wireless reception signal is not the bit synchronization signal, and oscillation of the main clock is stopped. On the other hand, TG is TB
If so, it is determined that the wireless reception signal is the bit synchronization signal.

Although the main clock has a higher frequency than the sub clock, it is faster than the sub clock, but the power consumption of the device is greater than that of the case of operating with the sub clock. Therefore, as described above, first, a rough first check is performed using the sub clock, and only when there is a possibility that the radio reception signal is a bit synchronization signal, the main clock is oscillated to perform a strict second check. To Also, if the radio reception signal is not a bit synchronization signal,
The main clock stops oscillating and returns to the operation state using the sub clock.

Therefore, it is not necessary to always oscillate the main clock in checking the bit synchronization signal, and the time during which the main clock rises can be shortened. Therefore, the bit synchronization signal can be confirmed without increasing current consumption, and in particular, the battery life of a digital data wireless communication device mainly powered by a battery can be extended.

According to a fourth aspect of the present invention, in addition to the method of the third aspect, when it is determined that the signal is not a bit synchronization signal as a result of the interval time determination, the predetermined time TC is increased. If it is determined that the signal is a bit synchronization signal as a result of the interval time determination, the predetermined time TC is reduced.

According to the above method, when it is determined that the signal is not a bit synchronization signal as a result of the interval time determination under main clock oscillation, the predetermined time TC is increased.
Conversely, when the interval time is determined to be a bit synchronization signal, the predetermined time TC is reduced.

If TC is increased, the probability that the number KG accidentally falls within the range R which can be KB is reduced, although it is not a bit synchronization signal. Therefore, it is possible to narrow the range for determining that there is a possibility of being a bit synchronization signal. Conversely, TC
Is small, the probability that the number KG accidentally falls within the range R that can occur as KB increases. Therefore, it is possible to widen the range for determining that there is a possibility that the signal is a bit synchronization signal.

Therefore, even though it is determined that there is a possibility of a bit synchronization signal in the edge number determination as a rough first inspection under the subclock oscillation, a finer second inspection under the main clock oscillation is performed. If it is determined that the signal is not a bit synchronization signal as a result of the above interval time determination, the predetermined time TC is increased in order to increase the accuracy of the first check under subclock oscillation.

Conversely, if the interval time is determined as the second check, and it is determined that the signal is a bit synchronization signal, it is determined in the first check that there is a possibility of a bit synchronization signal. In other words, it means that the second investigation has a high probability of determining that the signal is a bit synchronization signal.
That is, even if the above-mentioned predetermined time TC is reduced, no trouble is likely to occur. Therefore, the predetermined time TC is reduced. This shortens the time of the first survey,
Power consumption can be reduced accordingly.

Therefore, in addition to the effect of the method according to the third aspect, by changing the determination accuracy of the radio reception signal in accordance with the installed radio wave environment, high accuracy and low power consumption can be achieved.
The bit synchronization signal can be checked efficiently.

[0032]

DESCRIPTION OF THE PREFERRED EMBODIMENTS [Embodiment 1] An embodiment of the present invention will be described with reference to FIGS.
It is as follows. The wireless communication device for digital data according to the present embodiment is a wireless telemeter that receives digital data, and is mainly powered by a battery. First, the configuration will be described.

FIG. 2 shows the entirety of the radio telemeter 41. A microcomputer (control unit) 42, which is a one-chip microcomputer for control, includes an RF unit 43, a memory 45,
A clock 46 and a switch 47 are connected and provided. The microcomputer 42 is a one-chip microcomputer of a two-clock system. The RF unit 43 receives a radio reception signal that is digital data, and includes an antenna 44. The memory 45 stores data in a received signal, information such as the frequency of a bit synchronization signal of a signal to be received, and software described later. The clock 46 includes a main clock and a sub clock having a lower frequency and lower current consumption. The switch 47 functions as an external switch for switching the measurement time of the wireless reception signal.
This is for the user to arbitrarily change a predetermined time TC described later.

FIG. 1 is a block diagram of a timer 21 of a microcomputer 42, which is a one-chip microcomputer of the two-clock system. Internal bus 22, counter register 23 as a counter, clock selector 24, frequency dividing circuit 2
5, an external clock input 26, a main clock 27, and a sub clock 28 are provided.

The counter register 23 has a function of using a radio reception signal as an external signal as a counter clock (hereinafter, referred to as an external clock function). This function is a function that can be counted for each edge of the wireless reception signal, and is usually often built in a one-chip microcomputer and does not require a clock of the microcomputer.
Then, the clock selector 24 sets the counter register 2
The third clock is selected from the main clock 27 or the subclock 28 and the clock of the wireless reception signal input from the external clock input 26. When the clock selector 24 selects the clock of the wireless reception signal input from the external clock input 26 as the clock of the counter register 23, the counter register 23 functions as an external clock counter that counts the clock.

The standard of the radio reception signal received by the radio telemeter is as described with reference to FIGS. Therefore, the description is omitted here.

Next, the operation of checking the bit synchronization signal from the radio reception signals will be described with reference to the flowchart of FIG. First, a first survey with the following coarse accuracy is performed. Only the sub clock 28 is oscillated, and the external clock function is operated for a fixed time TC. That is,
The timer 21 is cleared and started (S1), and the external clock counter, which is the counter register 7, is cleared and started (S2). Advance the timer until the timer value reaches TC (= 1.67 ms) (S
3). And, input from the external clock input 26,
The number KG of the edges of the radio reception signal during the predetermined time TC is counted. The edge is a rising edge or a falling edge, and the user can determine which one to use.

Then, it is determined whether the value of the external clock counter obtained by the counting, that is, the number KG of edges of the radio reception signal is two or three or other (S4). This will be described below.
This is done by examining whether the number KB of edges in the bit synchronization signal of the radio reception signal, which should be at the predetermined time TC, and the above-mentioned KG coincide with or close to each other or not, as described below. It is determined whether or not there is a possibility of receiving the edge number (edge number determination). That is, it is determined whether or not KG falls within the range R of the number KB of edges that should be within the predetermined time TC.
This will be specifically described with reference to FIG. This is the waveform of the bit synchronization signal of the system in which the bit rate of the radio reception signal is 2400 bps. The period of the bit synchronization signal is T
TC = k · Ta + α (k is an integer of 0 or more, 0 ≦ α <
TC), the number KB of the rising edge or the falling edge of the bit synchronization signal, which should be during the predetermined time TC and corresponds to KG counted as described above, is k. Or (k + 1), and any one of them can be taken. Whether the number of KBs is k or (k + 1) is determined by the difference between the start time of the TC and the timing of the bit synchronization signal, and may change each time the first check is performed.

For example, as shown in the figure, the predetermined time TC is set to 4 times the interval time of 417 μs between the rising edge of the bit synchronization signal and the falling edge adjacent thereto.
If it is set to 1.67 ms, which is exactly equal to the period Ta, and if the currently received radio reception signal is a bit synchronization signal, as can be seen from the figure, k = 2 and the rising edge is Two or three are detected. In other words, if two or three rising edges are detected, the currently received wireless reception signal may be a bit synchronization signal. On the other hand, if the currently received wireless reception signal has a random waveform in the absence of wireless radio waves as shown in FIG. 5, the same TC (1.67 ms) as above is applied. Thus, five rising edges are detected, which do not fall within the range R of two or three.

Therefore, it is determined whether or not the value of the external clock counter obtained by counting, that is, the number KG of edges of the radio reception signal satisfies the following equation: k ≦ KG ≦ k + 1. In this case, as described above, it is determined whether KG is 2 or 3 or other.

Thus, it is determined whether or not KG falls within the range R that can occur as KB. If the above expression is satisfied, it is determined that there is a possibility that the signal is a bit synchronization signal.
On the other hand, if the above expression is not satisfied, as in the case of FIG. 5, for example, it is determined that the signal is not a bit synchronization signal.

In the first check, the sub clock is used, and the T
During C, since only control is performed so that the radio reception signal is input as the counter clock, there is no need to oscillate the main clock. The current consumption when the microcomputer is operated by the sub clock is about 20 μA, while the current consumption when the microcomputer is operated by the main clock is about 2 mA and 10 μA.
There is 0 times inspiration. Therefore, current consumption can be significantly reduced.

Next, as a result of the first investigation, when it is determined that there is a possibility that the bit synchronization signal has been received, the main clock is subsequently oscillated to operate the microcomputer at high speed (S5). . Then, as a second survey with high accuracy, the interval time between the rising edge of the radio reception signal and the falling edge adjacent thereto is measured as the edge interval time TG of the radio reception signal,
By determining whether or not this is 417 μs as described above (S6), it is determined whether or not the signal currently being received is a bit synchronization signal (interval time determination). For this reason, it can be confirmed that the signal is a bit synchronization signal with high accuracy.

The above-mentioned edge interval time is an interval time between rising edges, an interval time between falling edges, or an interval time between rising edges and falling edges, and the user can determine which one to use. . Since the cycle of the bit synchronization signal is Ta, the interval time between rising edges and the interval time between falling edges is Ta. The interval time between the rising edge and the falling edge is (Ta / 2).

If it is determined that the signal is a bit synchronization signal, the process proceeds to a frame synchronization signal detection process (S7).

On the other hand, a radio reception signal is generally a random signal when there is no radio wave, so in the above-mentioned first investigation, although it is not a bit synchronization signal,
By chance, KG may fall within the range R that can occur as KB. For example, when measured with a certain device, about 20
This phenomenon occurred with a probability of%. In such a case, it is determined that the signal is not a bit synchronization signal only after proceeding to the second check. In that case, the oscillation of the main clock is immediately stopped (S8), and the process returns to the first investigation using only the sub clock. As a result, the erroneous determination of the bit synchronization signal by chance coincidence in the first check is immediately eliminated, and the time during which the main clock rises and oscillates is shortened as much as possible.

As described above, only when it is determined in the first check that there is a possibility that the bit synchronization signal is being received, the main clock is oscillated and the next processing (second check) is performed. If it is determined in the investigation that there is no possibility that the bit synchronization signal has been received, the main clock is not oscillated. This makes it possible to reduce the frequency of oscillation of the main clock as compared with the case where the main clock is always oscillated to determine whether or not the bit synchronization signal has been received.
As described above, the time for unnecessary processing by the main clock can be reduced, so that the time during which the main clock is oscillating can be shortened, and the current consumption can be reduced.

Here, in the present embodiment, since switch 47 is provided as described above, the user can arbitrarily set a predetermined time TC for counting the number of edges of the radio reception signal. Can be changed.

The longer the predetermined time TC is, the more the number of edges to be counted is increased, so that the accuracy of determining the bit synchronization signal is increased. That is, KG of random noise in the absence of radio waves accidentally enters the range R where the number KB of corresponding edges in the bit synchronization signal can occur, oscillates the main clock, and proceeds to the next processing (second investigation). Probability can be reduced. Therefore, the current consumption in the second investigation can be reduced.

More specifically, for example, the time TC for inputting the above-mentioned radio reception signal is set to 1.67 ms.
Is changed to 3.34 ms, which is twice as large as that, if there are 4 to 5 rising edges (k = 4), it is determined that the bit synchronization signal may be received. Here, since the radio reception signal waveform when there is no radio wave is random as shown in FIG. 5, there is a possibility that the rising edge of the radio reception signal becomes 4 to 5 by chance coincidence.
TC is lower than the case where the TC is 1.67 ms.
That is, the determination accuracy of the bit synchronization signal increases. Therefore, it is possible to reduce the probability that a radio reception signal that is not a bit synchronization signal is determined to be a bit synchronization signal in the first investigation and the main clock is oscillated and the processing proceeds to the next second investigation. Therefore, the time required to oscillate the main clock more than necessary is reduced, and the current consumption can be reduced accordingly.

On the other hand, if the predetermined time TC is long, the time for receiving the radio reception signal at the time of the first check with the coarse accuracy becomes long, so that the circuit of the radio section under the sub-clock oscillation operates accordingly. The time to do it becomes longer. Therefore, it cannot be said that the current consumption of the wireless telemeter device as a whole also decreases. That is, the waveform of a wireless reception signal when there is no wireless radio wave is basically random, but its pattern depends on the noise environment and the like. Therefore, in the present embodiment, the TC is set to the switch 47.
, And the user can arbitrarily adjust the TC. Then, by operating the switch 47,
By appropriately adjusting the TC according to the current installed radio wave environment, it is possible to set according to the installed radio wave environment, and to set the best time without significantly increasing the current consumption. Has become.

Embodiment 2 Another embodiment of the present invention is described below with reference to FIGS. 2, 3 and 6. For convenience of explanation, members having the same functions as the members shown in the drawings of the above-described embodiment are denoted by the same reference numerals, and description thereof will be omitted.

This embodiment is basically the same as the first embodiment. However, instead of the switch 47, the microcomputer (control unit, time control unit) 42 shown in FIG.
However, the operation of the switch 47 is automatically performed. Then, instead of being changed by the switch 47, the microcomputer 42 as the time control unit
The detection result of the bit synchronization signal with coarse accuracy based on the number of edges of the radio reception signal for a fixed time as a check, and the second
A time T for counting the number of edges of the radio reception signal with coarse accuracy by comparing the result with the detection of the bit synchronization signal with high accuracy based on the edge interval time of the radio reception signal as a survey
C is automatically changed by software, so that the radio telemeter itself automatically
The best time is set as TC. Note that, in addition to the automatic variable operation, the switch 47 can be manually operated as in the first embodiment.

The procedure will be described with reference to the flowchart of FIG. This procedure is basically the same as FIG. 3 of the first embodiment. Therefore, the description of the same part is omitted or simplified.

Steps S21 and S22 are the same as steps S1 and S2, respectively. In S23 corresponding to S3, KG is counted until the timer value reaches the above TC in the same manner as in S3. In S24 corresponding to S4, similarly to S4, it is determined whether the value of the external clock counter is k or (k + 1). Step S25,
S26 is the same as steps S5 and S6, respectively.
After it is determined that there is a possibility of a bit synchronization signal in the first check of the coarse accuracy due to the subclock oscillation, the determination in the second check with high accuracy due to the main clock oscillation is performed.

At S26 in the judgment in the second survey,
If the edge interval time is 417 μs and it is determined that the radio reception signal is a bit synchronization signal, the process proceeds to the frame synchronization detection process in S27 corresponding to S7, as in S7. In the present embodiment, after or before this, the TC is reduced by a predetermined ΔTC (S29), so that the time TC for receiving the radio reception signal by the subclock is shortened from the next time. I do.

On the other hand, in S26, the edge interval time is 4
If it is not 17 μs and it is determined that the wireless reception signal is not a bit synchronization signal, in S28 corresponding to S8, the oscillation of the main clock is stopped as in S8. Then, in the present embodiment, after or before this,
By increasing C by a predetermined ΔTC (S30), TC, which is the time for receiving the radio reception signal by the subclock, is lengthened.

.DELTA.TC in S29 and S30 are stored in the memory 45 in advance. Note that ΔTC in S30
May not be the same as ΔTC in S29. Also, ΔT
Instead of adjusting C, TC may be multiplied by a constant. In this way, TC, which is the time for receiving the radio reception signal of the first investigation, can be set to the best.

The digital data radio communication apparatus according to the present invention may be configured as follows. That is,
A digital data wireless communication device is a wireless communication device for a telemeter controlled by a one-chip microcomputer of a two-clock system. The number of edges of the received signal is counted, and a wireless bit synchronization signal is detected with coarse accuracy.

Further, in the above configuration, the time for counting the number of edges of the radio reception signal by the subclock can be made variable by an external switch. Further, in the above configuration, the time for counting the number of edges of the radio reception signal by the subclock can be automatically changed by software.

In the above configuration, after the bit synchronization signal is detected only by the sub clock oscillation, the main clock is oscillated to measure the edge interval of the radio reception signal, and the bit synchronization signal is confirmed with high accuracy. Therefore, it is possible to search for a frame synchronization signal.

According to the above configuration, the time during which the main clock rises can be shortened, and the total current consumption can be suppressed, so that the battery life can be extended. Also, by making the accuracy related to the determination of the radio reception signal externally variable, it is possible to make settings according to the installed radio wave environment. In addition, since the accuracy relating to the determination of the radio reception signal is made variable by software, if it is operated, the setting can be automatically set according to the installed radio wave environment.

[0063]

As described above, the digital data radio communication apparatus according to the first aspect of the present invention intermittently receives a radio reception signal transmitted by adding a bit synchronization signal before data to be transmitted. Then, every time a receiving operation is performed, synchronization is acquired for the bit synchronization signal, and the radio reception signal is converted to the bit only when the edge interval time of the radio reception signal is equal to the corresponding edge interval time of the bit synchronization signal. A digital data wireless communication device that performs an interval time determination for determining a synchronization signal includes a main clock and a sub clock having a lower frequency than the main clock, and the sub clock oscillates during a predetermined time TC. A counter for counting the number of rising edges or the number of falling edges KG of the radio reception signal; If the number of applicable edges does not fall within the range R that can occur as the number KB during the time TC, the radio reception signal is determined not to be the bit synchronization signal, and if the number KG falls within the range R, The number of edges for determining that the radio reception signal may be the bit synchronization signal is determined, and the number KG is in the range R
A control unit that oscillates the main clock to perform the interval time determination, and, when it is determined that the wireless reception signal is not the bit synchronization signal, stops the main clock oscillation. It is a configuration provided.

Therefore, the bit synchronization signal can be confirmed without increasing current consumption.
This has the effect of extending the battery life of a digital data wireless communication device that is mainly powered by a battery.

According to a second aspect of the present invention, in the digital data radio communication apparatus according to the first aspect of the present invention, when the interval time is determined not to be a bit synchronization signal as a result of the interval time determination, The time TC is increased, and when it is determined that the signal is a bit synchronization signal as a result of the interval time determination,
This is a configuration including a time control unit for reducing the predetermined time TC.

Therefore, in addition to the effect of the configuration of claim 1, by changing the determination accuracy of the radio reception signal according to the installed radio wave environment, high accuracy and low power consumption can be achieved.
There is an effect that the bit synchronization signal can be efficiently confirmed.

According to a third aspect of the present invention, there is provided a radio communication method for digital data, wherein a bit synchronization signal is added before data to be transmitted, and a radio reception signal transmitted is intermittently received.
For each reception operation, the bit synchronization signal is synchronously acquired, and the radio reception signal is converted to the bit synchronization signal only when the edge interval time of the radio reception signal is equal to the corresponding edge interval time of the bit synchronization signal. In the digital data wireless communication method for determining the interval time, the sub-clock is oscillated and the fixed time TC
During the period, the number KG of rising edges or the number of falling edges of the radio reception signal is counted, and the number KG
Is in a range R that can occur as the number KB of the corresponding edges in the bit synchronization signal during the time TC. If the number KG does not fall in the range R, the radio reception signal Is determined not to be the bit synchronization signal, and if the number KG falls within the range R, the number of edges is determined to determine that the radio reception signal may be the bit synchronization signal, and the number KG is determined. Is within the range R, a main clock having a higher frequency than the sub clock is oscillated, the interval time is determined, and if it is determined that the radio reception signal is not the bit synchronization signal, the main clock is oscillated. This is a method of stopping clock oscillation.

Therefore, the bit synchronization signal can be confirmed without increasing current consumption.
This has the effect of extending the battery life of a digital data wireless communication device that is mainly powered by a battery.

According to a fourth aspect of the present invention, in addition to the method of the third aspect, when the interval time is determined not to be a bit synchronization signal as a result of the determination of the interval time, the predetermined time is determined. The time TC is increased, and when it is determined that the signal is a bit synchronization signal as a result of the interval time determination,
This is a method for reducing the predetermined time TC.

Therefore, in addition to the effect of the method according to the third aspect, by changing the determination accuracy of the radio reception signal in accordance with the installed radio wave environment, high accuracy and low power consumption can be achieved.
There is an effect that the bit synchronization signal can be efficiently confirmed.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a schematic configuration of a timer section in a configuration example of a digital data wireless communication apparatus according to the present invention.

FIG. 2 is a block diagram showing a schematic configuration of a configuration example of a wireless communication device for digital data according to the present invention.

FIG. 3 is a flowchart illustrating a bit synchronization signal determination process in the digital data wireless communication apparatus of FIG. 2;

FIG. 4 is an explanatory diagram showing a waveform of a bit synchronization signal.

FIG. 5 is an explanatory diagram showing a waveform of a wireless reception signal in a state where there is no radio wave.

6 is a flowchart showing a bit synchronization signal determination process in the digital data wireless communication apparatus of FIG. 2;

FIG. 7 is an explanatory diagram showing a configuration of a radio reception signal.

FIG. 8 is an explanatory diagram showing a waveform of a bit synchronization signal of a wireless reception signal.

[Explanation of symbols]

 21 Timer 22 Internal Bus 23 Counter Register 24 Clock Selector 25 Frequency Divider 26 External Clock Input 27 Main Clock 28 Sub Clock 30 Header 31 Bit Synchronization Signal 32 Frame Synchronization Signal 33 Call Signal 34 Data 35 Rising Edge 36 Falling Edge 41 Radio Telemeter 42 Microcomputer (control unit, time control unit) 43 RF unit 44 Antenna 45 Memory 46 Clock 47 Switch

Claims (4)

[Claims] An intermittent reception of a radio reception signal transmitted by adding a bit synchronization signal before data to be transmitted, and performing synchronization acquisition on the bit synchronization signal for each reception operation, In a digital data radio communication apparatus for performing an interval time determination for determining the radio reception signal to be the bit synchronization signal only when the edge interval time of the reception signal is equal to the corresponding edge interval time of the bit synchronization signal, A counter for counting the number of rising edges or the number of falling edges KG of the radio reception signal during a fixed time TC under the oscillation of the subclock; KG falls within a range R that can occur as the number KB of the corresponding edges in the bit synchronization signal during the time TC. If not, it is determined that the wireless reception signal is not the bit synchronization signal, and if the number KG falls within the range R, the number of edges that determines that the wireless reception signal may be the bit synchronization signal Make a decision,
When the number KG falls within the range R, the main clock is oscillated to determine the interval time. If it is determined that the wireless reception signal is not the bit synchronization signal, the main clock is oscillated. A wireless communication device for digital data, comprising: 2. When the interval time is determined not to be a bit synchronization signal as a result of the interval time determination, the predetermined time TC is increased, and when the interval time determination is determined to be a bit synchronization signal, 2. The digital data wireless communication apparatus according to claim 1, further comprising a time control unit for reducing the predetermined time TC. 3. A wireless reception signal transmitted by adding a bit synchronization signal before data to be transmitted is intermittently received, and the bit synchronization signal is acquired every time a reception operation is performed. A digital data wireless communication method for determining an interval time for determining that the wireless reception signal is the bit synchronization signal only when the edge interval time of the reception signal is equal to the corresponding edge interval time of the bit synchronization signal, Is oscillated to count the number of rising edges or the number of falling edges KG of the radio reception signal during a predetermined time TC, and the number KG is determined during the time TC of the corresponding edge in the bit synchronization signal. It is determined whether the number KG falls within a range R that can occur as the number KB. Signal is not the bit synchronization signal, and if the number KG falls within the range R, the number of edges is determined to determine that the radio reception signal may be the bit synchronization signal. If KG falls within the range R, a main clock having a higher frequency than the sub-clock is oscillated, the interval time is determined, and if it is determined that the wireless reception signal is not the bit synchronization signal, A method for wirelessly communicating digital data, characterized by stopping oscillation of a main clock. 4. When the interval time is determined not to be a bit synchronization signal as a result of the interval time determination, the predetermined time TC is increased, and when the interval time determination is determined to be a bit synchronization signal, 4. The digital data wireless communication method according to claim 3, wherein said predetermined time period TC is reduced.