JPH03229531A - Codeless telephone - Google Patents

Abstract

PURPOSE:To prevent the generation of a dead zone by disposing at least two base units, connecting them to a common telephone line, accessing different channels, and setting a handset so that it accesses all channels. CONSTITUTION:The handset 1 executes continuous reception and transmission with the base units 2 and it is set basically as usable for any channel. The base units 2A and 2B are arranged as illustrated, for example. Namely, an area 4 curved by a chain line is a service area which is the object of a codeless telephone. Thus, two base units 2A and 2B are arranged in the area 4, and the handset 1 accesses all the channels. On the other hand, the base unit 2A accesses only odd channels and the base unit 2B accesses only even channels. Thus, a call can be originated and terminated even if the handset 1 is in any place of the area 4.

Description

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

A. Industrial application field B. Summary of the invention C Conventional technology D Problems to be solved by the invention E. Means to solve the problem F Effect G Example G. First embodiment (Figures 1 to 8) G2 Second embodiment (Figures 9 and 10) G3 Other embodiments 1-1 Effects of the invention A. Industrial application field This invention relates to cordless telephones.

B. Summary of the Invention This invention enables a cordless telephone to expand its service area by using a plurality of pace units by executing a predetermined process when a Heath unit (master unit) and a handset (child unit) are connected. It is made to be expandable.

C. Prior Art For example, in the United States, ten duplex channels, channels 1 to 10, are prepared for use in cordless telephones. The range in which hand cents can be used, that is, the service area, is 100 to 30
It is 0m.

In Japan, there are two types of cordless telephones: weak type and low power type, and the service area is 10 to 20 meters for the weak type and 100 meters for the low power type.
That's about it.

D. Problem to be solved by the invention However, the above-mentioned service area is a line-of-sight distance,
When used inside a building, the surrounding environment of the handset and Heas Unisoto, such as the structure of the building, affects the radio waves, so the service area becomes narrower than the line-of-sight distance.

For this reason, when the building is large, even though they are in the same building,
Areas where cordless telephones cannot be used, i.e.
This may create a dead zone.

This invention attempts to solve these problems.

Means for Solving the Problems Therefore, in the present invention, at least the first and second pace units are arranged so as to cover the area targeted by the cordless telephone, and the first and second pace units are arranged so as to cover the area targeted by the cordless telephone. Connect the base unit to a common telephone line. And the first and second Hess units are:
Each channel accesses different channels, and the handset accesses all channels.

F Effect One of the pace units becomes active and the handset is connected to the outside line through this active pace unit.

G Example C3 First Example In FIG. 1, (1) is a hand cent, (2A),
(2B) indicates a heath unit, and (3) indicates a telephone line (external line).

Note that the pace units (2A) and 2B) have the same configuration, so in the following description, when there is no need to distinguish between the two, the pace unit (2A) and the pace unit (2B) will be represented by the Hess unit (2).

In the handset (1), (110) is its transmitting circuit, (120) is its receiving circuit, and the transmitting circuit (
110) converts the audio signal St and command signal CMNO (details will be described later) into an upstream channel FM signal Su and transmits the same, and a receiving circuit (120) receives the downstream channel FM signal Sd. This demodulates the audio signal Sr and the command signal CMND. Furthermore, in the receiving circuit (120), for example, by detecting limiter noise generated by an intermediate frequency amplifier,
Detection signal 5 indicating the presence or absence of the downlink channel FM signal Sd
QLC is also taken out.

That is, based on this signal 5QLC, it is determined whether the channel currently receiving reception is in use but is an empty channel.

Also, when placed on the hand center (1), (131) is a dial key, (132) is a talk key, and this talk key (132) is a non-locking type button switch; Each time you press , the hand cent (1) alternates between standby mode and talk mode. When the hand 7-(+) is in standby mode, it is waiting for a call from the handset (1) and, for example, as shown in FIG. It repeatedly monitors reception in order and waits for a connection request from the pace unit (2). Furthermore, in the talk mode, continuous reception and transmission are performed with the base unit (2), and basically any channel can be used at this time.

Furthermore, (133) to (137) are auxiliary keys such as channel keys configured with non-locking type bush switches, (139) is a ringer speaker, (14)
0) is a microcomputer for system control. In this microcomputer (140), the command signal CMN transmitted by the transmitting circuit (110)
D is formed, and the command signal CMND and detection signal 5QLC taken out from the receiving circuit (120) are judged. In addition, in the microcomputer (140), a control signal TCT is used to permit/prohibit transmission/reception of the transmitting circuit (110) and receiving circuit (120), specify a channel, etc.
L, RC are also formed.

Also, (141) is a ROM, and this ROM (141)
A 25-bit system identification code 5YrD for distinguishing this cordless telephone from other cordless telephones is stored in the .

On the other hand, the pace unit (2) has a transmitting circuit (210) and a receiving circuit (220) similar to the transmitting circuit (110) and receiving circuit (120) in the hand cent (1), and the receiving circuit (220) is , when in standby mode, it is waiting for an incoming call from the telephone line (3), and
For example, as shown in FIG. 4, the head unit (28) repeatedly monitors reception of odd-numbered channels in order and waits for a connection request from the hand center (1), and the pace unit (2B) As shown in the figure, even-numbered channels are repeatedly monitored in order to wait for a connection request from the hand sent (1).

Also, when in talk mode, the pace unit (2A
) performs continuous reception (3 and transmission) to and from the handset (1) using any of the even channels, i.e. The base unit 1-(2A) is dedicated to odd channels and the pace unit (2B) is dedicated to even channels (handset (1) is dedicated to all channels as described above).

In addition, in this way, in order to make the base unit (2B) exclusive to odd-numbered channels and the base unit (2B) exclusive to even-numbered channels, the transmitting circuit (210) and the receiving circuit (
The LSB of the input port of the frequency division ratio of the PLL (220) may be set at, for example, the H' level in the pace unit (2A) and the L'° level in the pace unit (2B).

Alternatively, the LSBs of the control signals TCTL and RCTL may be made the same.

Furthermore, in the pace unit (2), (240) is a microcomputer for system control, and this microcomputer (240) performs the same processing as the microcomputer (140) in the handset (1), and also controls the entire cordless telephone. It also manages the operation of Also, (241) is a ROM, and this ROM (241
) has a system identification code 5YID written in it.

Furthermore, (261) is a 4-wire/2-wire conversion circuit, (262)
(263) is a dial tone signal (DTMF signal)
(264) is a ring tone signal detection circuit.

Then, the pace units (2A) and (2B) are installed as shown in FIG. 3, for example. In other words, when opening and opening, the area (4) surrounded by chain lines is the service area targeted by this cordless telephone.

Area (48), (4C) or pace unit (28)
If areas (4B) and (4C) are the service areas of the base unit 112B), then the base unit 112B) will be serviced by the base unit 112B). (2A) , (
2B) is placed in area (4).

In addition, area (4C) is pace unit (28),
This is an overlapping area of the service area of (2B).

In addition, the switch circuits (262), (262) of the pace units (2A), (2B) are connected to the telephone line (3).
connected in common (in parallel) to

FIG. 2 shows an example of the signal format of the command signal CMND, which has a 24-bit bit synchronization signal BSYN at the beginning, followed by a 16-bit frame synchronization signal FSYN. In this case, these signals BSYN, FSYN are, for example, BSYN=”1
01010・・・・・・・・・10°”FSYN
= “1100010011010110” ... FSYN for upstream channel - “1001.001100110110°”
...has a specific focus pattern indicated for the downstream channel.

Further, the command signal CMND includes, following the signal FSYN, a 25-bit system identification code 5YID and a 12-bit error correction code EC for this code 5YID.
C and a 3-pin dummy bit DB1T in this order, and a 5-byte control code CTRL following the dummy pin DBIT.

In this case, the first hide of the control code CTRL is a code indicating the control contents of the hand sent (1) and the head unit (2), and the second hide to fifth bytes are as follows:
These are parameters or data related to the first hide.

(-), and when the handset (+) or base unit (2) receives this command' signal CMNO, the microcomputer (140) or (240) recognizes that the identification code 5YID contained in the signal CMND is stored in its own ROM. It is checked whether the command signal CMND matches the identification code 5YID stored in (141) or (241), and only when they match, the command signal CMND is made valid, and when it does not fail, it is made invalid.

"Standby" During standby, as explained with reference to FIG. 4, the hand sent (1) repeatedly monitors reception of channels 1 to 10 in order. In addition, the base unit (28)
The base unit (2B) repeatedly monitors reception of odd-numbered channels in order, and the base unit (2B) repeatedly monitors reception of even-numbered channels in order.

“Make a call” When making a call, for example, the 5th
The calling routine (300) shown in the figure is executed (the calling routine of the base unit (2) may be the same as a general one, so illustration is omitted).

In other words, hand cent (1) is now in the service area (
4A) and is in standby mode.

In this state, when the talk key (132) of the handset (1) is pressed, this is detected by the microcomputer (140), and the routine (300) starts from step (301) and then from step (302). )
At , an empty channel is searched.

Then, when an arbitrary empty channel N (either an odd or even channel is found) is found, the transmitting circuit (1
10) and the receiving channel (120) are fixed to the vacant Nth channel, and the transmitting circuit (110) and receiving circuit (120) are permitted to transmit and receive on this Nth channel. Therefore, the handset (1) is in talk mode on the Nth channel.

Subsequently, in step (303), the control code CT
A command signal CMND in which l'lL indicates a call request is formed, and this signal CMND is repeatedly supplied from the microcomputer (140) to the transmitting circuit (110).
10), the signal C? IND is converted into an upstream N-channel FM signal S, and this signal Su is transmitted to the base unit (2) through the antenna (100).

Then, the Nth channel at this time is an odd channel (
N=2n+1. (1 is one of O to 4), the hand sent (1) is transmitting an FM signal S trace requesting a call in the service area (48) of the base unit (2A). , base unit) (2A) repeatedly monitors reception of odd-numbered channels in order. Therefore, the reception channel of the base unit (2A) is
channel, the FM signal S of the call request from the handset (1) is received by the base unit (2A), and this signal Su is sent to the antenna (2A) of the base unit (2A).
200) to a receiving circuit (220), and a detection signal 5QLC is output.

Then, the reception channel of the base unit (28) is
This is fixed to this Nth channel, and then the receiving circuit (22
0), the FM signal S traces the command signal CJIND
is demodulated, this signal CMND is supplied to the microcomputer (240), and the identification code 5YID included in the signal CMND is
It is checked whether it matches the identification code 5YID of the ROM (241).

In this case, since they match and the control code CTRL included in the signal CMND indicates a call request, the microcomputer (240) sends the transmission circuit (210) to the channel on which the FM signal S was received. In this case, transmission is permitted on the downlink Nth channel. Therefore, the base unit (2A) also enters the talk mode on the Nth channel.

Further, in the pace unit (2A), the command signal CMND in response to the call request is sent to the microcomputer (2A).
240) to the transmitting circuit (210), in the transmitting circuit (210), the signal CMND is converted into a downlink FM signal Sd of the Nth channel, and this signal Sd is transmitted to the handset (1) through the antenna (200). Sent.

At this time, since Base Unisoto (2B) is monitoring reception only on even-numbered channels, the handset (1
) transmits an FM signal Su requesting a call from anywhere in area (4), it does not respond to it.

In the handset (1), when the FM signal Sd is transmitted from the base unit (2A) through the downlink N channel, it is received by the antenna (100) and supplied to the receiving circuit (120). (120) outputs the detection signal 5QLC of the FM signal Sd, and also outputs the command signal CMND.

Then, in step (304), the signal S[l]L
It is determined that the FM signal Sd has been received based on C, and the process proceeds from step (304) to step (305). In this step (305), the command signal CMND is determined, and in this case, the command signal commercial
The identification code 5YID included in the ND is the ROM (14
1) The control code CT included in the signal CMNO matches the identification code 5YID stored in the
Since RL indicates a response to the call request, 2. The process proceeds from step (305) to step (306),
In this step (306), the transmitting circuit (110)
and the receiving circuit (120)
- One mode is established.

Therefore, handset (]) and Hebe Unisoto (2
A) is now connected through the Nth channel.

Further, in the pace unit (2A), the switch circuit (262) is set to an off-func state, and the transmitting circuit (2A) is turned off.
10) and a receiving circuit (220) are connected to the line (3) through a conversion circuit (261) and a switch circuit (262).

Therefore, the handset (1) is based on the base Unisoto (
2A) to the line (3).

Next, when the caller enters the telephone number of the other party using the dial key (131) of the hand cent (1), the system? I
A command signal CMND indicating that the ll code CTRL is to send a telephone number and the telephone number is formed, and this signal CMND is converted into an upstream FM signal Su and transmitted.

Therefore, in the pace unit (2A), the command signal CMND is obtained from the receiving circuit (220), and the control code CTRL of this signal CMND indicates that a telephone number is to be sent and indicates the telephone number. , the formation circuit (263) is controlled by the microcomputer (240) according to the telephone number, and the hand cent (1)
A dial tone signal corresponding to the telephone number sent from
).

When the other party answers the phone, the voice signal Sr from the other party is sent to the transmission circuit (210) through the line (3) → base unit (2A) switch circuit (262) → conversion circuit (261) signal line. is supplied to Therefore, the signal Sr is converted into a downstream FM signal Sd, and this signal Sd is transmitted from the antenna (200).

Then, this signal Sd is received by the handset (1), a voice signal Sr is taken out from the receiving circuit (120), and this signal Sr is supplied to the receiver (121).

Also, when transmitting a call, the audio signal S from the transmitter (111)
t is supplied to the transmitting circuit (110) and the upstream FM signal S
u, and this signal Su is transmitted from the antenna (100) to the pace unit (2A).

Then, the signal Su is received by the base unit I-(2A) and the signal St is taken out from the receiving circuit (220), and this signal St is sent to the line (3) through the conversion circuit (261) and switch circuit (262) and sent to the other party's phone.

On the other hand, in step (303), the command signal CMND of the call request is sent to the Nth channel.
When transmitting, if the Nth channel is an even channel (N=2n+2), then the Heath unit (2
Since A> is monitoring the reception of odd channels, the base unit (2A) does not respond to the call request from the handset (1) and continues monitoring reception of the odd channels.

Also, at this time, the base unit (2B) is monitoring reception of even-numbered channels, but the service area (4B) (4C) of the handset (1) or base unit (2B) is
), the F of this call request is
M signal signal S trace base unit) (2B) is not received,
The base unit (2B) continues to monitor reception of even channels.

Therefore, in this case, even if Hand Seno) (1) transmits the FM signal S trace requesting a call, base unit l-(
2A) and (2B) will not be able to receive the FM signal S trace in response to the call.

Therefore, the processing in the handset (1) is performed from step (304) or (305) to step (311).
), and in this step (311) the channel of the handset (+) is incremented by one channel, so in this case the handset (])
is changed from an even channel to an odd channel.

Next, in step (312), step (311
), and reception is performed on the channel set in
It is checked whether the channel is a free channel, and if it is a free channel, the process goes to step (3).
12) and returns to step (303). Therefore, in this step (303), an FM signal S requesting a call is transmitted on an odd-numbered channel.

Therefore, when an FM signal S trace requesting a call is transmitted in the service area (4A) of the base unit (2A),
If the FM signal S is an even channel, it is switched to an odd channel and the FM signal S requesting a call is sent.
Then, a channel is opened between the handset (1) and the base unit (28) as described above, and the handset (1) and the base unit (28) are connected.

Further, in step (312), if the Nth channel is not an empty channel, the process is performed in step (312).
Step 12) proceeds to STEP (313), in which the channel is incremented by two channels, so in this case it is taken as the next odd channel. Then, the process is at step (312)
Return to

Therefore, when the channel is changed from an even channel to an odd channel in step (311), if the odd channel is not an empty channel, step (311)
12) In step (313), an unoccupied odd numbered channel is searched, and when an unoccupied odd numbered channel is found, in step (303), an FM signal S for requesting a call is transmitted on the unoccupied odd numbered channel. become.

In this way, the service area of the base unit (28) (
48) to make a call request, the handset (1
) and the base unit (2A) through the odd-numbered channels, and calls can be made.

Also, if the handset (1) is in the service area (4B)
When a call request is made on the handset (1
) and the base unit (2B), and a call is made through the base unit (2B).

Furthermore, when the handset (1) makes a call request in the overlapping area (4C), if the FM signal S at that time is an odd channel, the call processing is performed with the base unit (28). If it is an even channel, call processing is performed with base unit 1-(2B).

"Incoming call" When a call arrives, the base units (2A) and (2B) each execute the incoming call routine (400) shown in FIG. (The illustration is omitted as it can be the same as the original)
.

In other words, when a call comes through line (3),
In both base units (2A) and (2B), the ring tone signal is detected by the detection circuit (264), and this detection signal is supplied to the microcomputer (240).

This then causes the routine (400) to move to step (4).
01), and then in step (402) a search is made for an empty channel. However, this search for empty channels is performed only for odd channels in the base unit (28), and only for even channels in the base unit I-(2B).

Then, select any free channel N (base unit (2)
In A), N=2n+1, base unit) (2B
), when N = 2 n + 2 ) is found, the transmitting circuit (210) and receiving channel (220) are fixed to the vacant Nth channel, and
Transmission and reception by the transmitting circuit (210) and receiving circuit (220) is permitted on this Nth channel. Therefore, the base units (2A) and (2B) are in talk mode on the Nth channel.

Subsequently, in step (403), the control code CT
I? A command signal CMND in which L indicates a request for an incoming call is formed, and this signal CMND is repeatedly supplied from the microcomputer (240) to the transmitting circuit (210), and the signal CMND is used to convert the FM signal S trace of the Nth downstream channel. and transmitted to the handset (1). In this case, the base unit (2A) is the odd channel, the base unit (2B
) transmits on even-numbered channels, so there is no possibility of FM signal interference.

At this time, if the handset (1) is in the service area (48) of the base unit (2A), for example, the handset (1) repeatedly monitors reception of all channels in order, so the base unit The FM signal S trace detection signal 5QLC from (2A) is output from the receiving circuit (120).

Then, the receiving channel of the handset (1) is fixed to the Nth channel corresponding to the base unit (2A), and then the command signal CMND from the FM signal S is demodulated in the receiving circuit (120), and this signal CMNO
The identification code 5YID included in the ROM (141)
It is checked whether it matches the identification code 5YID.

In this case, since they match and the control code CTRL included in the signal CMND indicates a request for an incoming call, the transmitting circuit (110) sends the message to the base unit (2A).
Transmission is permitted on the Nth channel on which the FM signal S trace was received. Therefore, the hand cent (1) also enters the talk mode on the Nth channel.

Furthermore, a command signal CMND in response to the incoming call request is formed in the handset (1), and this signal C
MIQD connects the microcontroller (140) to the transmitter circuit (110).
), and this signal CMND is converted into the upstream FM signal S of the Nth channel and sent to the base unit (2A).
.

(2B).

Then, when the base unit (2A) receives an FM signal S trace from the handset (1) through the upstream N channel, the receiving circuit (220) transmits the FM signal.
While the M signal signal S trace detection signal 5QLC is output,
The command signal CI'lND is output and the microcomputer (24
0).

Then, in step (404), it is determined that the FM signal S trace has been received based on the signal 5QLC, and the process proceeds from step (404) to step (405). In this step (405), the command signal CM
ND is determined, and in this case, its command signal CMND
The identification code 5yro included in the ROM (241)
Since the control code CTRL included in the signal CMND indicates a response to the call request, the transmission circuit (2
10) and the receiving circuit (220), the talk mode in the Nth channel is determined.

Therefore, the hand cent (1) and the base unit (2
8) is now connected through the Nth channel.

Furthermore, in the handset (1), a microcomputer (1
40) controls the oscillation circuit (138) to form a ringer signal, and this signal is supplied to the speaker (139), which produces a bell sound indicating an incoming call.

Then, in the handset (1), when the talk key (132) is pressed, a command signal CMND in response to the call is formed, and the control code CTRL indicates that the talk key (132) has been pressed. The oscillation circuit (138) is transmitted by the FM signal Su.
is turned off and the ringer is turned off.

Then, the command signal C from this hand cent (1)
When the M IJ D is received at the base unit (28), it is detected in step (406);
Next, in step (407), the switch circuit (26
2) is assumed to be in an off-func state.

Therefore, the handset (1) and the base unit (2)
A communication channel is opened with A), and from then on, communication can be made between the other party and the hand cent (1).

On the other hand, the base unit (2B) performs step (403)
Even if an FM signal S trace requesting an incoming call is sent at , in this case, it is outside the service area (4Fl) or (4C) of the handset (1) or the base unit (2B), so it is not sent from the handset (1). cannot receive the FM signal Su in response to the incoming call.

Therefore, the processing in the base unit (2B) is performed from step (404) or (405) to step (405).
11), and in this step (,111) it is checked whether a ringer signal from line (3) is still available, and if so, the process moves from step (411) to step (403). ), and the incoming call request is processed again.

However, as mentioned above, a channel is opened between the base unit (2A) and the handset (1) and the handset (1) passes through the base unit (2A) to the line (3).
), this results in no ringer signal from line (3).

Then, in the base unit (2B), step (411) indicates that this ringer signal cannot be obtained.
is detected, and the process proceeds from step (411) to step (412), and in this step (412), the base unit (2B) is prohibited from transmitting the FM signal S trace, and is in a state where even-numbered channels are monitored for reception. In other words, it enters standby mode.

Also, the hand cent (1) is attached to the base unit (2B).
If you receive a call while you are in the service area of
The relationship between the base units (2A) and (2B) described above is reversed, and the handset (1) and base unit (2B)
Similar incoming call processing is performed between the base unit (2
A call is made through B).

Furthermore, if an incoming call is received while handset (1) is in the overlapping area (4C), handset (1) receives the FM signal S trace from both Base Unison I-(2A) and (2B). At this time, the handset (
If 1) is receiving and monitoring odd-numbered channels, incoming call processing is performed with base unit y) (2A), and if it is receiving and monitoring even-numbered channels, base unit (2A) is
2B).

"Moving during a call" This is a case where the handset (1) moves between areas (48) to (4C) during a call.

When moving during this call, the routine (500) shown in FIG. 7, for example, is executed on the hand cent (1), and the routine (600) shown in FIG.
) or in one of the base units (2A) and (2B). However, since the routine (500) is almost the same as the calling routine (300) except for step (521), the corresponding step is given a reference number in the 500s instead of a reference number in the 300s, and the step (
501) to (513) will be omitted.

And now, the hand cent (1) is in the service area (4
In C), assume that a call is in progress through the base unit (2A).

Then, during this call, in the base unit (2A), steps (601) of the routine (600),
(602) is repeated. That is, step (
601), the control code CTRL is a command signal C? indicating a channel change. It is checked whether IND has been received, and if not, the process proceeds from step (601) to step (602), and in this step (602), the control code CTRL determines whether a command signal CMND indicating the end of the call has been received or not. If it is not received, the process goes to step (
602) returns to step (601).

Therefore, in the base unit I-(2A) during a call, steps (601) and (602) are repeated, and the command signal CMND for changing the channel or ending the call is monitored from the hand center (1).

Then, during a call, the handset (1) is in the area (4C).
If you move 1 from area (4B), the base unit (
The FM signal Sd from 28) became weak and the receiver (121
) makes a lot of noise. Therefore, in such a case, the channel key (133) is pressed.

Then, the pressing of the key (133) is detected by the microcomputer (1).
40), which causes the routine (500)
starts from step (501), then step (
521), a command signal CMND whose control code CTRL indicates a channel change is formed, and this signal C
M rq D is transmitted by the FM signal Su, followed by
The steps after step (502) are executed in the same way as when making a call.

Therefore, if the channel key (133) is pressed during a call, a command signal CMND for changing the channel will be transmitted, and then a command signal CMND for requesting a call will be transmitted on an empty channel.

Then, in the base unit (2A), a channel change command signal CMND is sent from the hand sent (1).
is sent, this signal port NO goes to step (601
), the process proceeds from step (601) to step (611), and in this step (611), the switch circuit (262) of the base unit (2A)
is put on hold, and then in step (612),
A time wait is performed for a predetermined period of time.

Then, when the period of step (612) has elapsed, the process proceeds to step (603), and this step (603)
, transmission and reception of the base unit (2A) is prohibited, and the switch circuit (2A) of the base unit (2A) is prohibited.
262) is put on-hook, and the call termination process for Heisunisoto (2A) is performed, and then step (2A) is performed.
At 604), the base unit li2Δ) enters a standby state.

On the other hand, in Hand Sent (1), after transmitting the channel change command signal CMND, step (502)
While the subsequent steps are being executed, the hand sensor h(]) is in the service area (4B) of the base unit 2B). Also, the base Konint (2B) is on standby Moto.

Therefore, hand cent (1) and -, -s unit cent (
2B), the same processing as when making a normal call is performed,
A channel is opened between the handset (1) and the base unit (2B) and the base unit 112B
) is placed in an off-hook state, and base unit l-(2B) is connected to line (3).

Note that step (60) is performed after this connection is terminated.
The period of the step (612) is set so that step 3) is executed, and the line (3) is connected to the base unit (2B) from the hold state.

Therefore, from now on, the handset (I) can resume a noise-free call through the base unit I-(2B).

Also, when Hand Sent (1) is making a call through Base Unison (2B) in Area (4C) and moves from that area (4C) to Base Unison (28), noise may occur. If there are too many, just press the channel key (133). That is, the same processing as described above is performed in the base units (2A) and (2B), and the hand sent (1) is connected to the line (3) through the base unit (28), and the noise-free call is resumed. can.

"Ending a call" At the time of ending a call, for example, the routine (600) shown in FIG. do.

And now, hand 7) (1) is service area (4
8) or (4C), the base unit h (2A
).

Then, during this call, the base unit (2A) performs steps (601) (6) of the routine (600).
02) is repeated.

When the talk key (132) is pressed when the call ends, the control code CTRL forms a command signal CMNO indicating the end of the call, and this signal CMND is transferred to the FM
It is transmitted to the base unit (2A) by signal Su.

Then, in the base unit (2A), this command signal CMND for ending the call is detected in step (602), and the processing is performed from step (602) to step (60).
Proceeding to step 3), a call termination process is performed in this step (603), and then, in step (604), the standby mode is entered.

Further, the handset (1) enters standby mode after transmitting the call end command signal CMNO.

In addition, hand seso l-(+) is area (4B),
When terminating a call from (4C) through Base Unisol I-(2B), the same processing is performed for all (all).

As described above, according to the present invention, it is possible to make a call using a cordless telephone, but in this case, especially according to the present invention, two base uninotes (2A ),
(2B) and the handset (1) accesses all channels, but the base unison 1-(2A)
accesses only odd channels and bases UniSoto (
2B) accesses only even channels, so calls can be made and received no matter where the hand cent (1) is in area (4).

In addition, each of the base units (2A) and (2B) can operate as a normal base unit even when used alone, so the user only needs to purchase more units as needed, and the two base units (2A) can be used from the beginning. , There is no need to install (2B).

Furthermore, since the problem can be dealt with simply by changing the software, there will be no cost increase.

G2 Second Embodiment In the examples shown in FIGS. 9 and 1O, for example, interference occurs during a call, so when it is desired to change the channel, this is possible.

That is, when the channel key (133) is pressed on the hand center (1) during a call, the routine (50
0) is executed, and as described above, the command signal CMND for changing the channel is sent.3 The command signal CM for requesting a call is sent.
Transmission of NO and reception of the call response are performed.

However, in this case, in step (512), the Nth
If the channel is not a free channel, the process returns from step (512) to step (511), the channel is incremented by one channel, and then the process returns to step (512).

Therefore, in this case, the hand sent (1) makes a call request in order, regardless of whether the channel is an odd numbered channel or an even numbered channel, if the channel is free.

On the other hand, in the base unit (2), during a call, a command signal CMND for changing the channel is transmitted (then this signal CllN0 is detected in step (601), and the processing starts from step (601) to step (62).
Proceeding to step 1), in this step (621), the switch circuit (262) is placed in a suspended state.

Subsequently, in step (622), the channel of base uninote (2) is incremented by 2 channels from the current Nth channel, and then in step (62)
3) In (624), check whether the FM signal Su from the handset (1) can be received on the incremented channel, and if so, whether it is the command signal CMND of the call request in step (503). It will be checked.

Then, when the command signal CMND for the call request cannot be received, the process proceeds to steps (623) and (624).
) to step (625), and this step (62
In 5), it is checked whether a predetermined period of time has elapsed since the process progressed from step (601) to step (621), and if it has not elapsed, the process proceeds from step (625) to step (622). Return to

Therefore, steps (622) to (624) are repeated until the period checked in step (625) has elapsed. If so, it is checked in turn for each even numbered channel whether a command signal CMND requesting a call from the handset (1) can be received.

At this time, the handset (1) executes the routine (500) as described above, and transmits the command signal CMND requesting a call on an empty channel.

Therefore, in the base unit (2), the command signal CMND of this call request is detected in step (624), the process proceeds from step (624) to step (626), and in this step (625),
A process for establishing a new channel with the handset (1) and a process for releasing the hold are performed, and then the process returns to step (601).

Therefore, the handheld device (1) is now connected to the base unit (2) again through the new channel and can resume the call.

Note that step (625) is for dealing with the above-mentioned "movement during a call".

In other words, if the handset (1) is making a call in area (4C), for example through base unit 7) (2A), and moves to area (4B) of base unit (2B) and presses the channel name key (133). do.

Then, in this case, the handset (1) is in the area (
4B), the command signal CMND for the call request in step (503) is transmitted, so from now on, the command signal CMND for the call request in step (503) is
Connection processing is performed between the base unit I-(2B) and the handset (1) is connected to the line (3) through the base unit (2B).

On the other hand, the base unit (2A) connected to the handset (1) in the area (4C) receives the channel change command signal CMND, and the process proceeds from step (601) to step (621). But then the handset (1) is connected to the base unit (
2B), so the base unit (2A
) is not connected to the hand sent (1) even if steps (622) to (625) are repeated.

Then, after a predetermined period of time has elapsed, the base unit (2
The process of A) is from step (625) to step (603).
), and after the call termination process is performed in this step (603), the standby mode is entered in step (604).

Therefore, in this example, when interference occurs on the current channel, or when the hand sent (1) moves through the area (4) and the noise increases, that is, when the current When the channel condition deteriorates, press the channel key (133) to
A new channel suitable for the call will open and you can resume the call through this new channel.

G3 Other embodiments In the above, two base units (2A) (2B) are installed in the area (4) targeted by the cordless telephone.
), but if N units (N22) of base units (2) are installed and channels are assigned in the same way, the cordless telephone can be used in a wider area (4).

I4 Effects of the Invention According to this invention, there are two base units (2A) in the area (4) targeted for cordless telephones.

(2B), hand cent (1) accesses all channels, base unit (2A) accesses only odd channels, base unit (2B)
) accesses only even-numbered channels, so calls can be made and received no matter where the hand sent (1) is in area (4).

In addition, each of the base units l-(2A) and (2B) can operate as a normal base unit even when used alone, so the user only needs to purchase more units as needed, and the user can use two base units from the beginning (2A). , There is no need to install (2B).

Furthermore, since the problem can be dealt with simply by changing the software, there will be no increase in costs.

[Brief explanation of drawings]

FIG. 1 is a system diagram of an example of this invention, FIGS. 2 to 4 are diagrams for explaining the same, and FIGS. 5 to 10 are flowcharts of an example of this invention. (1) is a hand center, (2A) and (2B) are base units, (110) and (210) are transmitting circuits,
(120), (220) are receiving circuits, (300) to
(600) is a processing routine.

Claims (1)

[Claims] When making a call, a channel is opened between the handset and the base unit using radio waves, and the base unit is connected to the line so that a call can be made between the handset and the other party. The cordless telephone has a plurality of base units installed so as to cover the area where the handset is to be used, and these base units are connected to a common telephone line. , a cordless telephone in which the channels are set to access different channels from each other, and the handset is set to access all channels set in the multiple bases.