JPH0329445A - Cordless telephone system - Google Patents

Abstract

PURPOSE:To avoid the inconvenience of unexpected interruption of talking by informing communication limit from a base station to a mobile station and allowing the mobile station to display the communication limit when the strength of a radio wave sent from the mobile station and received by the base station is a prescribed value or below during the communication through a radio channel between the base station and the mobile station. CONSTITUTION:A CD signal being the information of reception radio wave strength of a reception circuit 6 of a base station 1 during communication is decided by the control circuit 4 of the base station 1 and the circuit 6 informs the communication limit to the mobile station 2 through a radio transmission circuit 7 when the level represented by the CD signal reaches the communication limit being a prescribed value or below. Through the notice, the communication limit is informed to the user by alarming sound from a sounder 21 in the mobile station or display of a light emitting diode. Thus, unexpected interruption of the communication is prevented in advance.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to call limit display means for cordless telephone equipment.

Prior Art FIG. 2 shows the configuration of a conventional cordless telephone device. In Figure 2, 1 is a base station, 2 is a mobile station, 3 is a wireless line connecting these, 4 is a control circuit including a microcomputer built into the base station, and 5 is a microcomputer built into the mobile station. 1 is a control circuit, 6 is a base station radio reception circuit, 7 is a radio transmission circuit, 8 is a communication circuit with a telephone line, 9 is a power supply circuit, 10 is an ID memory that stores a call code, 11 is an antenna, 1
2 is a radio receiving circuit of the mobile station; 13 is a radio transmitting circuit; 14
15 is an amplifier circuit that drives the receiver, 16 is a microphone signal amplifier circuit 17, 18 is a rechargeable battery that is a power source for the mobile station, 19 is a call code t0 circuit on the mobile station side, 20 is an antenna, 21 is a phonetic body.

In the above configuration, when the base station 1 and the mobile station 2 are connected by the wireless line 3 and are in communication with the telephone line through the communication circuit 8, the base station 1 and the mobile station 2 As the distance between them increases, the strength of the received radio waves in the receiving circuit 12 decreases, and when this information is notified to the control circuit 5 as a CD signal, the sounding body 21 sends out an alarm sound. The display was showing the limits of communication.

Even in this manner, it is possible to display the limit of communication due to a decrease in radio field strength.

Problems to be Solved by the Invention However, there are two wireless links between the base station 1 and the mobile station 2: a downlink from the base station to the mobile station, and an uplink from the mobile station to the base station. However, the above method has a problem in that it is limited to displaying the communication limit of the downlink. That is, if the uplink reaches its call limit before the downlink, the user cannot be warned and the call will be cut off inadvertently, resulting in an inconvenience.

Means for Solving the Problems In order to solve the above-mentioned problems, the present invention, during a call, transmits a CD signal, which is information on the received radio field strength of the receiving circuit on the side of 6 base stations in 1 base station. , 4 is determined by the control circuit, and when the communication limit value is below a certain value, a means is provided to notify the mobile station 2 of the communication limit through the radio transmission circuit 7, and by this notification, The alarm sound is emitted from the 21 sounding devices in the mobile station, and the light emitting diode displays.
This system is designed to notify the user that there is a limit to the number of calls that can be made.

Therefore, according to the present invention, when the downlink radio waves from the base station to the mobile station reach the notification limit,
Even when the wireless line upstream radio waves from the mobile station to the base station reach the communication limit, it is possible to display an alarm from the mobile station to warn that the communication limit has been reached, preventing the call from being cut off inadvertently. can be prevented.

Embodiment FIG. 1 shows the configuration of an embodiment of the present invention. In FIG. 1, 1 to 21 have the same configuration as the conventional cordless telephone device, and 22 indicates when the received radio wave intensity in the 6 wireless receiving circuits in the 1 base station falls below a certain value. ,
This is a means for notifying the second mobile station of the call limit. The radio waves of the uplink radio line emitted from the 13 radio transmission circuits in the mobile station 2 pass through the radio line 3 and are transmitted to the base station 1, but at this time, the radio waves between the mobile station 2 and the base station 1 are transmitted. If the distance is far and it is below the reception limit of the 6 radio reception circuits in the base station, the radio signal level will cause it to be received as a CD signal.
The control circuit of No. 4 is notified of the call limit. The control circuit of No. 4 immediately opens the call circuit of No. 8, and while holding the call for a certain period of time without disconnecting the call, communicates the call limit of No. 22 to the mobile station No. 2 using means for notifying the mobile station No. 2 of the call limit of No. 2. We will notify you accordingly. In the mobile station 2, this notification is received by the radio receiving circuit 12, transmitted to the control circuit 5, and an alarm sound is emitted from the sounding element 21 to notify the user of the call limit. In addition to the alarm sound, it is possible to notify the user of the call limit by blinking an LED lamp, etc., and it is also possible to use this in combination with the alarm sound.

The means for notifying the call limit in No. 22 currently uses the downlink wireless link from the mobile station at the limit of notification to the base station, but the reverse, so the radio field strength for notification is We have secured enough. If the mobile station is at the communication limit where this notification cannot be made, the control circuit 5 will indicate the communication limit based on the level of the CD signal indicating the radio field strength of the radio receiving circuit 12. , there is no problem since the user is already informed of the call limit.

Effects of the Invention As is clear from the above-mentioned embodiments, the present invention has advantages over uplink and downlink transmission caused by the fact that the wireless line of a cordless telephone device is a downlink from a base station to a mobile station, and vice versa, an uplink. Regardless of the difference in communication limits, when the distance between the base station and mobile station increases and the strength of the radio waves received by each decreases, it is possible to notify the user of the communication limit without accidentally disconnecting the call. It has the effect of informing people.

[Brief explanation of drawings]

FIG. 1 is a schematic block diagram of a cordless telephone device according to an embodiment of the present invention, and FIG. 2 is a schematic block diagram of a conventional cordless telephone device. 1...Base station, 2...Mobile station, 3...
... Radio line, 4 ... Control circuit including a base station microcomputer, 5 ... Control circuit including a mobile station microcomputer, 6 ... Radio receiving circuit, 7...
・Radio transmission circuit, 8... Call circuit including 2-wire to 4-wire conversion of telephone line, 9... Power supply circuit, 10.
...Call sign memory, 11...Antenna,
12... Radio receiving circuit of mobile station, 13...
...Radio transmission circuit, l4...Amplification circuit that drives the receiver of 15, Amplification circuit that amplifies the microphone signal of 16...17, 18...Rechargeable battery ,1
9...Call sign memory, 20...Antenna, 21...Sounding body.

Claims (1)

[Claims] It consists of a base station connected to a telephone line and a mobile station wirelessly connected to the base station, and includes a control circuit for transmitting and receiving control data between the base station and the mobile station, and a control circuit for transmitting and receiving control data between the base station and the mobile station. A modulation/demodulation circuit for communicating the voice over a wireless line, a wireless transmission/reception circuit, buttons etc. for user operation, a microcomputer to control each of these circuits, and a call code storage circuit. In a cordless telephone device equipped with a mobile station, during communication between the base station and a mobile station over a wireless line, the mobile station receives the mobile station due to a distance between the base station and the mobile station, etc. When the strength of the radio waves transmitted by the station falls below a certain value, the base station notifies the mobile station of the call limit, and the mobile station displays the call limit by sound or light. Cordless telephone device with special features.