JPH10190563A - Phs cordless phone - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce the number of PLL circuits and codec parts and to provide a miniaturized inexpensive master unit by switching the frequency of the PLL circuit to the frequency corresponding to respective channels and forming a logic control channel on the two frequencies. SOLUTION: By the count output of an LCCH counter provided in a control part 15, the frequency in the PLL circuit 13 is switched to the different logic control channel. The logic control channel performs intermittent communication at respective LCCH intervals and the transmission timing of the multiplexed logic control channel is shifted for the interval of transmitting the two logic control channels. Thus, by changing frequency division value data in the PLL circuit 13 after a reception timing immediately after the transmission of one logic control channel until the transmission timing of the logic control channel of the other frequency, the logic control channel multiplexed to the two frequencies is formed by a set of the PLL circuit 13 and the codec part 14.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a logical control channel multiplexing method in a PHS cordless phone master unit, and more particularly, to a PHS cordless telephone having a simplified configuration for logical control channel multiplexing.

[0002]

2. Description of the Related Art A master unit of a PHS cordless phone intermittently transmits information on a logical control channel in order to notify wireless information and system information to a slave unit. This logical control channel is allowed to be multiplexed on two frequencies according to the standard in order to avoid radio wave interference. Also, P
When a call is being made with the HS handset, transmission and reception must be further performed on the frequency of the call channel. For this purpose, it is necessary to multiplex two logical control channels including a communication channel.

As shown in FIG. 1, a conventional master unit of such a PHS cordless phone includes a radio unit 21 and a modem unit 22.
In addition, a plurality of (three) PLL circuits 23A to 23C and codecs 24A to 24C are provided.
A pair of the circuit 23A and the first codec unit 24A, a pair of the second PLL circuit 23B and the second codec unit 24B for transmission and reception of the control channel 2, and a pair of the third PLL circuit 23C and the third codec unit for transmission and reception of the speech channel. A set of 24C is used, and transmission / reception is performed by switching the operation timing of each set by the controller unit 25 including a microcomputer or the like. Also, a PLL circuit is assigned to each of the four transmission / reception slots in the PHS system,
A technique of switching by a controller has also been proposed.

[0004]

In any case, in the prior art, the PHS master unit multiplexes the logical control channel and sets the logical control channel while communicating with the slave unit on the communication channel. To form, multiple sets of PLLs
Since a circuit and a codec unit are required, there is a problem that the base unit of the PHS cordless phone cannot be reduced in size and formed at low cost. That is, when communicating with Kotsuki on the communication channel, one frequency of the communication channel and two frequencies of the multiplexed logic control channel must be formed simultaneously, for a total of three frequencies.
As a result, a plurality of PLL circuits and a codec unit are required.

An object of the present invention is to provide a PHS cordless phone capable of reducing the number of PLL circuits and codecs, and obtaining a compact and low-cost base unit.

[0006]

SUMMARY OF THE INVENTION According to the present invention, a PHS cordless phone having a speech channel and a plurality of logical control channels and switching frequencies for each channel can generate at least a frequency signal corresponding to each channel. A single PLL circuit and a codec section; and a controller section for switching the frequency of the PLL circuit to a frequency corresponding to each of the channels, and a logical control channel is formed on at least two frequencies. Here, the PHS system has an LCCH counter that counts four transmission / reception slots as one unit, and switches the logical control channel based on the output of the LCCH counter. It is configured such that transmission and reception can be performed using every other two pairs of slots, such as the first slot and the third slot or the second slot and the fourth slot, among the pairs of transmission and reception slots.

[0007]

Next, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a block diagram showing the configuration of a master unit of a PHS cordless phone according to the present invention.
3 and a codec unit 14, and the codec unit 14 or the PLL circuit 13 is controlled by the control unit 15. Here, the control unit 15 is provided with an LCCH counter,
The frequency in the PLL circuit 13 can be switched to a different logical control channel by the count output of the LCCH counter. Note that the LCCH counter is a hardware counter that counts every 5 ms using four transmission / reception slots as one unit in the PHS system. In the codec IC (for example, μPD98311) provided in the codec unit 14, every four transmission / reception slots of the PHS system, such as the first and third slots or the second and fourth slots, are used. It is possible to transmit and receive using the two sets of slots.

A control method of a logical control channel to be transmitted in the master unit having such a configuration will be described with reference to a timing chart of FIG. FIG. 2 is a diagram showing the signal transmission timing of the communication channel and control channels 1 and 2 in the master unit and the count value of the LCCH counter. Using the transmission / reception function by the above-mentioned codec IC,
While notifying wireless information and the like on the logical control channel frequency, it is possible to communicate with the slave unit on the communication channel frequency. Further, the logical control channel is for intermittent transmission at every LCCH interval n × 5 ms, and the transmission timing of the multiplexed logical control channel is nOFFSE.
Since the time is shifted by T × 5 ms (nOFFSET is an interval for transmitting two logical control channels), P is not changed from the reception timing immediately after transmission of one logical control channel to the transmission timing of the logical control channel of the other frequency.
By changing the frequency division value data in the LL circuit, it is possible to form a logical control channel multiplexed on two frequencies by a set of the PLL circuit 13 and the codec unit 14, and at the same time, to form a communication channel. Also becomes possible.

For example, the aforementioned codec IC (μP
D98311) and using the LCCH counter as shown in the flowchart of FIG. If the value of the LCCH interval value n of the logical control channel is set by software, the LCCH counter value is reset to 0 after n-1. If the LCCH counter value is reset to 0 when transmitting the logical control channel on the control channel 1, the logical control channel signal can be transmitted at a constant period by always performing transmission when the LCCH counter is 0. . When the LCCH counter is 0, after receiving the uplink LCCH signal transmitted in synchronization with the downlink LCCH, the frequency is switched to the frequency of the control channel 2.
And the LCCH counter is set to n
It is set so that the downlink LCCH signal is transmitted at the time of OFFSET-1. LCCH counter is nOFFSET-
When the value is 1, after the uplink LCCH signal transmitted in synchronization with the downlink LCCH signal is received, the frequency division value of the PLL is reset to switch to the frequency of the control channel 1, and when the LCCH counter is 0, It is set to transmit a downlink LCCH signal. By repeating this, it is possible to form a logical control channel multiplexed on two frequencies by a set of PLL circuit and codec section.

[0010]

As described above, according to the present invention, one PLL circuit and a codec unit capable of generating a frequency signal corresponding to a communication channel and two logical control channels, and the frequency of the PLL circuit is set to each of the channels. Has a controller unit for switching to a frequency corresponding to the frequency, and has a configuration in which a logical control channel is formed on at least two frequencies. Since the PHS master unit for transmitting a signal on the logical control channel to be formed can be formed by a single PLL circuit and a codec unit, a plurality of PLL circuits and a codec unit, which have been conventionally required, become unnecessary, and parts Reduction and downsizing of the device are possible.

[Brief description of the drawings]

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

FIG. 2 is a diagram showing timings of transmitting a communication channel signal and a control channel signal in a base unit and values of an LCCH counter.

FIG. 3 is a flowchart illustrating an example of a control method.

FIG. 4 is a block diagram showing an example of a configuration of a conventional PHS cordless phone.

[Explanation of symbols]

 Reference Signs List 11 Radio unit 12 Modulation / demodulation unit 13 PLL circuit 14 Codec unit 15 Control unit

Claims (5)

[Claims] 1. A PHS having a communication channel and a plurality of logical control channels, and switching a frequency for each channel.
In the base unit of the cordless phone, at least one P capable of generating a frequency signal corresponding to at least the logical control channel is provided.
A PHS cordless phone comprising: an LL circuit and a codec unit; and a controller unit that switches a frequency of the PLL circuit to a frequency corresponding to the logical control channel, and forms a logical control channel on at least two frequencies. 2. The PHS cordless phone according to claim 1, wherein frequency switching for the two logical control channels is performed in a time division manner. 3. The PHS cordless phone according to claim 2, wherein the frequency is switched by switching the frequency division value of the PLL circuit. 4. The PHS cordless phone according to claim 1, further comprising an LCCH counter for counting four sets of transmission / reception slots as one unit in the PHS system, and switching the logical control channel based on an output of the LCCH counter. . 5. The codec unit comprises two sets of slots, such as a first slot and a third slot or a second slot and a fourth slot, among four sets of transmission and reception slots of the PHS system. 5. The PHS cordless phone according to claim 4, wherein the PHS cordless phone can transmit and receive using a telephone.