JPS6319926A - Transmitter-receiver - Google Patents

Abstract

PURPOSE:To secure connection between a handset and a base unit in the minimum time by making the base unit scan a channel delayed by a channel compared with the handset in a queuing mode. CONSTITUTION:Both a handset 1 and a base unit 2 are set in a queuing mode when a call mode is through and the scan is started at and after the channel following that so far used for talking. However, the unit 2 starts its scan with a delay given from a timer by a scan time equivalent to a single channel compared with the handset 1. As a result, the unit 2 is set at the 2nd channel when the handset 1 is set at the 3rd channel. That is, the unit 2 always performs scan with a delay secured by a single channel compared with the scan of the handset 1. Thus, the channel through which the handset 1 transmitted an identification code can be connected to the unit 2 in the minimum time after a scan time equivalent to a single channel.

Description

[Detailed description of the invention] The invention will be explained in the following order.

A Industrial field of application B Summary of the invention C Prior art D Problem to be solved by the invention E Means for solving the problem F Effect G Embodiment G1 First embodiment (Figs. 1 to 6) Figure) G2 Other Embodiments H Effects of the Invention A Industrial Application Field This invention relates to a transmitting/receiving device such as a cordless telephone.

B. Summary of the Invention This invention provides, for example, in a multi-channel access type cordless telephone that does not have a control channel, by shifting the phase of channel scanning between the handset and the base unit, when making a call,
This allows channels to be connected immediately.

C. Prior Art In general telephones, the telephone cord is connected to a rosette attached to a pillar, wall, or the like. Therefore, the range within which the telephone can be moved is determined by the length of its telephone cord, and is approximately several meters. However, in order to increase the range of movement, the phone cord is lengthened (which results in the cord getting tangled and getting in the way).

Therefore, in the United States and other countries, a telephone system called a cordless telephone is being considered.

As shown in Fig. 7, it is composed of a transceiver (11) called a handset and a transceiver (2) called a base unit, and a telephone line (3) is connected to the base unit (2). , base unit (2
) and the handset (11) are coupled by radio waves,
Telephone calls from subscribers are answered using the handset (1) in the same way as with a regular telephone.

Therefore, the subscriber can freely move the Handsent+11 when making a call, and can use the phone outdoors, for example. What's more, the phone cord won't get tangled or get in the way.

The distance (service area) that the hand cent (1) can be separated from the base unit (2) is 300 m.
That's about it. Furthermore, the frequencies of the radio waves used between the handset (1) and the base unit (2) are 49M11Z band for the up channel and 46 MHz band for the down channel, and 10 duplex channels are approved by the FCC.

Thus, this cordless telephone allows the telephone to be used conveniently.

However, in cordless telephones, 10
Even if a double block channel is allowed, this
A control channel for controlling which channel of the 0 channel is used for communication is not available.

Therefore, when using a cordless telephone as an MCA system (multi-channel access system), this is realized in the following manner.

That is, in FIG. 6, the left side is the handset (11
channels managed by the base unit (2) on the right.
) indicates a channel managed by Also, [1] ~ (
The numbers in 10) indicate channel numbers, the O symbol is an empty channel, the * symbol is the channel that you are using, and the x symbol is a channel that is being used by another station.

When in standby mode, as shown in Figure A, the handset fl) repeatedly scans all channels (receiving channels) in order and waits for a call from the base unit (2). . Similarly, the base unit (2) repeatedly scans all channels in order and waits for a call from the handset (1).

When the handset (1) is making a call, when the handset (1) is set to talk mode, the handset (1) searches for an empty channel and finds an empty channel, as shown in the same figure. (channel 3 in the figure), scanning is stopped on this empty channel, and the identification code is repeatedly sent out while waiting for the identification code to be returned.

Then, in the base unit (2), when the empty channel (third channel) is reached during scanning, an identification code is obtained, but when this identification code is obtained, scanning is stopped at this empty channel. An identification code is sent back, and from then on, the call mode is entered on that vacant channel.

Furthermore, when the hand cent (1,) receives the identification code back, it then enters a call mode using that vacant channel.

Therefore, from now on, the dialed number is sent through the vacant channel (third channel), and if the other party answers the call, the call is made.

On the other hand, when a call is received from the 'FL communication line (3), the handset +11 and the base unit (21) simply switch positions, and as shown in C in the same figure, the vacant channel (
Incoming calls and subsequent calls are made using channel 9 (in the figure).

D Problems to be solved by the invention However, if the MCA method is realized as described above,
When the handset +11 and the base unit (2) are connected, the time required for the connection varies greatly depending on which channel the handset (11) and the base unit (2) are scanning.

That is, assume that the speed at which the hand cent (1) or the base unit scans each channel is, for example, 60 msec per channel.

Now, for example, as shown in Figure 6, when the base unit (2) scans the second channel, if the handset (1) starts transmitting the identification code on the third channel, then the base unit (2) When the scanning progresses by one channel and reaches the third channel, the base unit (2) can detect the identification code. Therefore, in this case, the time required from when the hand cent +1) transmits the identification code until it is detected by the base unit (2) is the scanning time for one channel, that is, 60 msec.

However, as shown in the same figure, for example, the base unit 2
) scans the 4th channel, hand sensor l
If -t1+ starts transmitting the identification code on the third channel, when the base unit (2) scans once and reaches the third channel, the base unit 2) can detect the identification code.

Therefore, in this case, the time required from when the handset (1) transmits the identification code until it is detected by the base unit (2) is a scan time of 9 channels, that is, 540 msec.

The same applies when calling the handset (11) from the base unit (2).

Therefore, the handset (11) and the base unit (2
), the time required for connection varies greatly depending on which channel the handset (11) and base unit (2) are scanning.

This invention attempts to solve these problems.

E. Means for solving the problem Therefore, in this invention, for example, FIGS.
By performing the processing shown in the figure, the handset (
11 and the base unit (2).

F. The connection time from the working handset (1) to the base unit (2) is reduced.

G Embodiment G1 First Embodiment FIG. 1 shows an example of a handset (1), (110)
is a transmitting circuit, and (120) is a receiving circuit. Also, the second
The figure shows an example of the base unit (2), where (210) is a transmitting circuit and (220) is a receiving circuit.

When transmitting a call, the voice signal St from the transmitter (111) is transmitted to the hand center (1) by the low frequency amplifier (
112) through the PLL (113) (7) VCO (
(not shown) and is supplied to the upstream channel FM signal S
This FM signal S signal is transmitted to the antenna (
100) and transmitted to the base unit (2).

Then, in the base unit (2), the signal (radio wave) Su from the handset (1) is connected to the antenna (200
), and the received signal Su is passed through a bandpass filter (22
1) and the mixer circuit (
223), and a local oscillation signal of a predetermined frequency from the PLL (224) is supplied to the mixer circuit (223).
The signal Su is converted into an intermediate frequency signal, and this intermediate frequency signal is sent to the FM via an intermediate frequency amplifier (225).
The audio signal St is demodulated by being supplied to the demodulation circuit (226), and this signal St is sent to the telephone line through the signal line of the low frequency amplifier (227) - 2-wire to 4-wire conversion circuit (231) -> relay circuit (232). (3).

In this case, the relay circuit (232) is connected to the base unit (
A line relay that turns on and off the connection between the base unit (2) and the telephone line (3), and a line relay that puts the line (3) on hold when temporarily suspending a call after the base unit (2) and the line (3) are connected. It has a hold relay etc. to keep it in place.

Also, when receiving a call, the voice signal Sr from the telephone line (3)
is supplied to the receiver (128) of the handset (1) through the same process as when transmitting a call. That is, the audio signal Sr from the line (3) is supplied to the VCO (not shown) of the PLL (213) through the signal line of the relay line (232) - conversion circuit (231) - low frequency amplifier (212). FM signal S of the downlink channel paired with FM signal Su
This signal Sd is converted into a high frequency power amplifier (
214) and the antenna (20
0) and transmitted to the handset (1).

In the handset +1), the signal Sd from the base unit (2) is received by the antenna (100), and the received signal Sd is passed through a bandpass filter (121) whose passband is all the downlink channels and a high-frequency amplifier. (122) to the mixer circuit (123), and a local oscillation signal of a predetermined frequency is supplied to the mixer circuit (123) from the PLL (124), and the signal Sd is made into an intermediate frequency signal. passes through the intermediate frequency amplifier (125) to the FM demodulation circuit (126).
) to demodulate the audio signal Sr, and this signal Sr
is supplied to the handset (128) through a low frequency amplifier (127).

Further, in the handset (11), (140) indicates a control circuit that controls a communication channel and the like.

This control circuit (140) is composed of a one-chip type microcomputer, and (141)
(142) is a ROM in which a program is written, for example, a 4-bit parallel processing CPU.

(143) is a RAM for a work area, and (144) is an input/output port. Note that the ROM (142) is also provided with a routine (300) shown in FIG. 3, for example.

Furthermore, the microcomputer (140) has a dial key (15).
1), )-x4 switch (152) and ROM (
153) is connected. In this case, use the dial key (15
1) is a non-lock type button switch for inputting the telephone number of the other party, and the talk switch (152) is a 3-position changeover switch for selecting the operating mode of this hand cent < 1). switch(
When contact 152) is 0, the power to other circuits except the microcomputer (140) is turned off (off mode), and when contact S is on, it is in a state of waiting to receive the signal Sd from the base unit (2) (standby mode). , when the contact T is on, the handset (1) and the base unit (2) are in a talking mode (talk mode), and is normally connected to the standby contact S.

Further, the ROM (153) is for giving an identification code ID, and these keys and ROMs (151) to (
The output of 153) is supplied to the microcomputer (140).

Furthermore, (161) shows an MSK modulation circuit, which is
When a code signal such as an identification code ID and a dial signal DS is supplied from the microcomputer (140), this code signal is converted from a binary signal to an MSK signal SaI in the audio band as shown in FIG. 5A, or as shown in FIG. 5B. like signal S
MSK signal SI outside the audio band on the low frequency side of t
The signal 5Ill is converted to 5Ill by an amplifier (
112).

In this case, the signal Sal in FIG.
and the base unit (2), and for this reason, the transmission speed of the code signal modulating the signal Ss is, for example, 1.2 kbp.
It is said to be a high speed of s. In addition, the signal S@ shown in Figure B is used when the communication channel between the handset (1) and the base unit (2) is opened and a communication is in progress; The transmission speed of the code signal modulating 5I11 is, for example, as low as 110 bps.

Further, (162) indicates a reception detection circuit, which is connected to the demodulation circuit (126), and the frequency component of the output of the TFR open circuit (126) varies depending on the presence or absence of the signal Sd from the base unit (2). This is used to detect the presence or absence of the signal Sd, and the detection signal N5QL is supplied to the microcomputer (140). -Furthermore, (163
) indicates the MSK demodulation i11 circuit, which is connected to the demodulation circuit (126) and demodulates the code signal from the MSK signal 5I11 sent from the base unit (2), and the demodulated signal is sent to the microcomputer. (140).

Further, (164) indicates a ring tone signal forming circuit,
This is controlled by a microcomputer (140) to generate a ring tone signal when a call is received, and the ring tone signal is supplied to a ringer (165).

Furthermore, the signal CH specifying the channel is sent from the microcomputer (140) to PLL (113), (124).
At the same time, a signal TXEυ for controlling whether or not to send out the FM signal Su is supplied to the PLL (113). Further, a muting signal MUTE is supplied from the microcomputer (140) to the amplifier (127).

Furthermore, in the base unit (2), (240) indicates a control circuit. This control circuit (240) is configured similarly to the control circuit (140'') of the handset (1) and has the same functions, and is similar to the circuits (141) to (144') of the control circuit (140). The corresponding circuit includes 1
200 series codes are used instead of 00 series codes, and the explanation will be omitted. However, the ROM (242) contains, for example, the fourth
The illustrated routine (400) is provided.

Also, ROM (253) and circuits (261) to (264)
) is also hand-f=-7 (1) (7) ROM (153
) and circuits (161) to (164), and each signal is also the same, so a description thereof will also be omitted. However, the forming circuit (264) generates a tone encoded signal (D) corresponding to the telephone number when calling the other party.
TMF signal) forms TE.

Furthermore, (265) indicates a ring tone signal detection circuit, which is connected to the telephone line (3) and detects a ring tone signal (ring tone signal) when a call is received, and the detection signal is BL is supplied to the microcomputer (240').

And the handset (1) and base unit (2)
In the routines (300) and (400), the CPUs (141) and (241') perform the following processing.

That is, in the handset (11), when in standby mode, the PLLs (113) and (124) are controlled by the signal CH in step (301) and set to the uplink and downlink channels corresponding to the value of the signal CI. , Next, in step (302), the switching position of the talk switch (152) is checked,
In this case, it is connected to contact S in standby mode, so the process starts from step (302) to step (30).
Proceed to step 3'). In this step (303'), the signal M
It is checked by SQL, and if the signal Sd is not received, the process moves from step (303) to step (30
41, and in this step (304'') the signal C
H is the value of the next channel (adjacent channel),
The process then returns to step (301).

Further, when the signal Sd is received in step (303), the process is performed from step (303) to step (
305), and in this step (305), the identification code ID from the demodulation circuit (163) and the ROM (153
) of the other subscriber's base unit (2).
), the process proceeds from step (305) to step (304'').

Therefore, in handset +11, when on standby,
Steps (301) to (305) are repeated, and all downlink channels are sequentially and repeatedly scanned as shown in FIG. 6A.

In addition, in the base unit (2), during standby, Lucia (400) (7) Stay/Pipe (401) ~ (
405).

(441) is executed. In this case, step (401
) to (405) are steps (301'') to (305)
The process is similar to the above, and the explanation is omitted, but in step (402), the presence or absence of an incoming call from the outside line (3) is detected based on the detection signal BL, and if there is no incoming call, the process returns to step (402). (402) to step (403')
Proceed to. Furthermore, in step (403), the presence or absence of the FM signal Su is checked instead of checking the presence or absence of the FM signal Sd in step (303). Further, in this case, steps (301) to (305) are executed at the same speed as steps (401) to (405).

Therefore, in Base Uniso I (2), steps (401'') to (405) are repeated during standby,
As shown in Figure A, all uplink channels are sequentially and repeatedly scanned.

Furthermore, when making a call using the handset (1), the talk switch (152) is switched to the talk mode contact T. Then, this is determined in step (302), the process proceeds from step (302> to step (311), and in this step (311) step (301)
It is checked by signal N5QL whether the uplink and downlink channels set by are being used by another station, and if they are not being used, the process proceeds from step (311) to step (312). Then, in this step (312), the signal TXEN causes the FM
Sending of the signal Su is permitted, and then step (313
), the identification code ID of the ROM (153) is removed from the MSK signal S by the modulation circuit (161) and the amplifier (1
12), and therefore, as shown in FIG. 6B, the identification code ID is transmitted to the base unit (2) by the upstream channel FM signal Su set in step (301).

In this case, the identification code ID in step (313)
The transmission of the identification code ID from the base unit (2)
Assuming that there is no return, the channel scanning in the base unit (2) is repeated over at least one round period.

Then, while the base unit (2) is on standby, it sequentially scans all uplink channels by repeating steps (401) to (405). When the uplink channel is reached, the process proceeds from step (403) to step (405), the scan is stopped, and it is determined that the identification code ID has been sent.

Then, the process moves from step (405) to step (42).
1), and in this step (421) the signal TX
Transmission of the FM signal Sd is permitted by the EN, and then in step (422), the identification code ID is converted into an MSK signal Sm by the modulation circuit (261) and supplied to the amplifier (212). , Therefore, as shown in FIG.
The handset (11
will be sent back to.

Then, the process starts from step (422) to step (43).
0), and in this step (430), the base unit (2) and the telephone line (3) are connected, that is, the muting of the amplifier (227) is canceled by the signal MLITH, and the relay circuit (232 ), the conversion circuit (231) and the line (3) are connected.

Also, hand cent (in 11, stelaph.

At the same time as the identification code ID is transmitted in step (313), the output signal of the demodulation circuit (163) is checked to see if the identification code ID has been returned in step (314).
) and (314) alternately in a time-sharing manner, and the shorter of the period during which the channel scan in the base unit (2) completes one cycle and the period until the return of the identification code ID is confirmed. ).

In this case, the base unit (2) has returned the identification code ID, so the process proceeds from step (314) to step (330), and in this step (330), the hand cent < 11 and the base unit (2) have returned the identification code ID. ) is connected, i.e. the channel between the handset [
At 11, the signal MUTH causes the amplifier (127) to
muting is canceled.

Therefore, the handset (11 is the base unit (
This means that it is connected to the telephone line (3) through 2).

Therefore, in the handset (1), the dial key (1)
51) corresponding to the other party's telephone number, the microcomputer (140) forms a corresponding dial signal DS, which is converted into an M S K signal Sm by the modulation circuit (161), and is similarly sent to the base unit ( 2).

In the base unit (2), the demodulation circuit (
The dial signal DS is taken out from the dial signal DS (263), and based on this signal DS, the microcomputer (240) outputs the dial signal DS from the forming circuit (263).
64) is controlled to form a tone encode signal TE corresponding to the telephone number of the other party, and this signal TE is sent to the amplifier (
227'), and further sent to the telephone line (3) through a conversion circuit (231) and a relay circuit (232). Therefore, the other party is called by this signal TE, and if the other party answers the call, the telephone conversation becomes possible from then on as described above.

Note that in step (311), step (301)
), the process proceeds to step (311") when the channel set by
) to step (304), and this step (3
04), the signal CH is assigned to the next channel,
Return to step (301). Therefore °ζ, step (
312) to (314), (421).

The process (422) will be performed on an empty channel, and subsequent calls will be made on that empty channel.

Further, in step (314), the base unit (
If the correct identification code ID is not returned from step 2), the process proceeds from step 314 to step 3.
15), the transmission of the signal Su is stopped by the signal TχEH in this step (315''), and the process then proceeds to step (304).Therefore, the identification code ID is returned from the base unit (2). If this does not occur, repeat the base unit (
2) is called.

In this way, when the handset (11) makes a call, when the talk switch (152) is set to the talk contact T, an empty channel is searched, the empty channel calling unit (2) is called, and a response is received from the base unit (2). , hand cent +11 and base unit (2)
A channel will be opened between you and the other party and you will be able to call and talk to the other party.

Further, when there is an incoming call from the telephone line (3), steps (411) to (415) of the routine (400) and step (321') of the routine (300),
(322) is executed. In this case, these steps (
411) to (415) and (321), (322
') are steps (311) to (315) and (421
”) and (422), and when there is an incoming call, the signal BL is determined in step (402), so the process proceeds from step (402) to step (411), and thereafter. As shown in Figure 6C, the telephone line (3) is connected to Base Uni 7H21 in the same way as when making a call.
is connected to the handset (1) through.

When the handset (1) makes a call or receives a call from the telephone line (3), the handset (1)
When the base unit (2) and the base unit (2) are connected and a call is being made, in the handset (1), processing proceeds from the Ste/Knob (330) to step (351), and in this step (351) Switch (152)
The contact position is checked, and if it is connected to the talk contact T, the process returns to step (351). Therefore, the contact position of the talk switch (152) is constantly monitored during a call.

Then, when you finish the call, press the talk switch (152
) is switched to the standby contact S, the stiffness is determined in step (351), and the process proceeds to step ('351).
) to step (352), and this step (35
2), an end code indicating the end of the call is formed in the microcomputer (140), and this end code is sent to the modulation circuit (
161”) to become the MSK signal Sm and the FM signal Su.
is transmitted to the base unit (2).

The process then proceeds to step (353), where the signal TXnN
, the transmission of the FM signal Su is stopped, and the signal MUTH mutes the amplifier (127) to close the channel, and the process then proceeds to step (
Return to 301).

Therefore, in the handset (1), since the call has ended, when the talk switch (152) is connected to the standby contact S, the end code is sent and the standby mode is entered, and the next channel that was used for the call is switched to the next channel. Channel scanning starts from the channel shown in FIG. 6A.

Further, in the base unit (2), the process proceeds from step (430) to step (451) during a call,
In this step (451) (summer tone circuit (263)
It is checked whether or not the end code from the handset (11) can be obtained by outputting the iy harmonic. If the end code is not obtained, the process returns to step (451). Therefore, during a call, the end code is always output. The reception will be monitored.

Then, when the call ends and an end code is sent in step (352), this is determined in step (451), and the process proceeds from step (451) to step (452), and this step (452'') The transmission of the FM signal Sd is stopped by the signal TXHN, the amplifier (227) is muted by the signal MUTE, and the connection between the conversion circuit (231) and the telephone line (3) is turned off by the relay circuit (232). The base unit (2) is released from the rotation ijl (31).

The process then proceeds to step (453), in which, for example, a software timer waits (delays) for one channel's worth of scanning time, and then the process returns to step (401').

Therefore, the base unit (2) enters standby mode after the scanning time for one channel has elapsed after receiving the end code, and switches from the channel A in the same figure to the channel that was previously used for the call. It will start scanning channels as shown.

Note that even if the other party hangs up before switching the talk switch (152) to standby point S, this cannot be detected by the base unit (2), so the talk switch (152)
52) to the standby contact S, the above-mentioned call termination process is performed.

In this way, when the call ends and the talk switch (152) is switched from the talk contact T to the standby contact S, the hand base (1) and base unit (2) enter standby mode, and the channel Scanning starts from the next channel as shown in FIG. Therefore, when on standby (Fig. 6A), when using a handsera)
When (1) is in the third channel, the base unit (2) is in the second channel, and so on, the scanning of the channels of the base unit (2) is always faster than the scanning of the channels of the handset (1). This means that you are one channel behind.

Therefore, the next time the handset (1) makes a call, the base unit (2)
Since the handset (1) scans the channel on which it transmitted the identification code after the scanning time of one channel, the handset (1) scans the channel on which it transmitted the identification code after the scanning time of one channel after making the call, that is, the minimum It will be connected to the base unit (2) in time.

Thus, according to the present invention, during standby, the base unit (2) scans a channel that is one channel later than the handset +11, so that when a call is made, after the scanning time of one channel, that is, the minimum time can connect the handset (1) and base unit (2).

Moreover, in order to do this, the routine (400) must be followed by a step (
453), it is easy.

In addition, when looking at Hand Sent (1) from the base unit (2k), the scan of Hand Sent (11) is on a channel 9 channels later than the base unit (2), so when a call arrives, the base It will take time equivalent to the scanning time of 9 channels to connect unit (2) and handsera) (1), but this is only when a call is received from outside, and is not used for general telephone calls. However, when I receive a call from outside, it takes some time for me to answer the call, so this is not a problem.

G2 other implementation services Note that in the above description, the circuits (161) to (164).

The operations (261) to (264') can also be realized by software. Furthermore, the telephone number of the other party can also be sent out by means of a dial pulse.

Further, in steps (313) and (413), the identification code ID is transmitted, and the presence or absence of the FM signals Sd and Su from the other party is checked, and the signals Sd and Su are transmitted.
Once Su is obtained, the identification code ID may be checked in steps (3141 and (414)).Furthermore, instead of delaying by a timer in step (453),
The delay may be performed until the FM signal Su is no longer obtained by the signal N5QL.The present invention is also applicable not only to cordless telephones but also to transceivers, carrier wave intercoms using a commercial AC power line, and the like.

Effects of the invention H According to this invention, during standby, the pace unit (2):
Since the channel is scanned one channel later than the handset (1), when making a call, the handset (11) and the base unit (2) are connected after the scanning time of one channel, that is, in the minimum time. be able to.

Moreover, for this purpose, it is only necessary to add a step (453) to the routine (400), which is easy.

[Brief explanation of the drawing]

FIGS. 1 and 2 are system diagrams of an example of the present invention, and FIGS. 3 to 7 are diagrams for explaining the same. (1) is the handset, (2) is the base unit, (1)
10). (210> is a transmitting circuit, (120”), (2
20) is a receiving circuit, and (140) and (240) are control circuits.

Claims (1)

[Claims] A first and a second transceiver are combined,
and a second transmitter/receiver, the transmitter/receiver uses one of a plurality of communication channels to make a call, and when on standby, each of the first and second transceivers transmits the plurality of communication channels. repeatedly scan the call channels in order to wait for a call from the other party, and when the call between the first and second transceivers ends and enters the standby state, the second transceiver teeth,
The transmitting/receiving device enters the standby state later than the first transmitting/receiving device by a scanning time corresponding to one communication channel.