JPH02285730A - Position confirmation system for cordless telephone set - Google Patents

Abstract

PURPOSE:To enhance the using rate and to prevent the theft of a telephone set by arranging plural exclusive receivers in a zone and detecting an outgoing frequency output at the receiver side, thereby managing the location of cordless telephone sets with an automatic equipment. CONSTITUTION:Lots of receivers 2 each composed of an exclusive receiver and an antenna are arranged in a prescribed location to receive a leakage radio wave being the output of a synthesizer outgoing frequency at the receiver side of a cordless telephone set 3. Thus, it is possible to detect the operation of the telephone set 3 in the vicinity of the antenna of the receiver 2. Thus, the location of the cordless telephone set is recognized at a center with comparatively simple and inexpensive constitution and this system is useful for the bill of the operating charge of the cordless telephone set, the improved efficiency of the rental service and the prevention of theft or the like effectively.

Description

[Detailed Description of the Invention] (1) Technical field to which the invention pertains The present invention is directed to confirming the location and usage status of wireless devices such as cordless telephones when they are used in various locations by confirming their location. It is related to the method.

(2) Conventional technology and its problems The need for a telephone service that allows calls ``anytime'' and ``anywhere'' has increased, and in Japan since 1930,
Cordless phones will be liberalized from October 2020. This cordless telephone can be said to be one step toward a mobile phone, and it is portable and allows you to make and receive calls wherever you go within the service area. Therefore, although the range of movement indoors is limited to a radius of approximately 50 to 100 meters, the convenience of the device has been appreciated and it is rapidly becoming used in large numbers in general households, stores, offices, and the like. Along with this trend, general users are devising new ways to use the telephones, which are different from the conventional telephones with cords.

An example of this is a telephone rental service.For example, there is a service in which telephones are rented out at a customer's request in a store such as a coffee shop. In this case, customer A, who has arrived at the store and is seated, orders the waitress to have tea and to borrow a telephone. The waitress lends a telephone according to Customer A's order. Customer A finishes his business using the loaned phone and leaves the phone on the desk. Another customer orders the waitress to borrow the phone, and the waitress calls Customer A.
After checking that it is not being used, he picks up the phone and takes it to Customer B and lends it to him.Customer A drinks tea, takes a rest, pays at the cash register, and leaves the store.

The above is a normal pattern. However, various abnormal situations occur here. One problem is that sometimes it is still in use when I go to customer A's place to pick it up. Another problem is that if the store is large, the items are lent one after the other and rotated, so you may not know which seat the customer took it from, and you may have to look for it.

Another big problem is that customers end up taking them out of the store because they don't have a code.

In order to avoid such situations, stores need to take precautions such as waiting for the customer to finish using the phone, picking it up immediately, and returning it to the checkout counter. It is easy to imagine that this will give a bad impression to the customers that they are watching over them, and that the waitresses will be neglectful in their service to other customers. Cordless telephones were tied with strings on top of the colored trays, making it easy to locate them and making it difficult for people to take them out.This created a harmonious color scheme within the store. This caused a lot of disturbance, creating a restless atmosphere in the store and giving customers an unpleasant impression.

(3) Purpose of the Invention The present invention allows the location management of cordless telephones to be performed by an automatic device without manual intervention, thereby eliminating the need for administrators to search for cordless telephones, increasing the usage turnover efficiency, and increasing the number of cordless telephones. The purpose of this invention is to provide a method for confirming the location of cordless telephones that can prevent theft of cordless telephones.

(4) Structure and operation of the invention FIG. 1 shows a block diagram of a cordless telephone according to the invention. For the purpose of the following explanation, a portion of the frequency synthesizer for controlling the transmitting and receiving frequencies will be described in some detail. In this figure, there are two independent frequency synthesizers: one for the receiver (RX) and one for the transmitter (TX). This frequency synthesizer uses one reference frequency oscillator (T
CX O) is shared. The oscillation frequency of each frequency synthesizer is controlled by the CPU.

Generally, these cordless telephones are battery-powered and portable.When not making calls, the power to the transmitter is turned off not only to save battery life but also to prevent radio wave interference. Since the receiver does not know when the call will be received, it is not always possible to receive a call (in some cases, the device does not have a main power switch.Of course, when the battery runs out, it is charged and the device is always ready for operation. Needless to say, it is necessary to keep it on.Furthermore, in order to prevent battery consumption, intermittent reception (battery saving) is generally performed at intervals of about 2 seconds.

Now, when this cordless telephone is in standby mode, the operating parts are the CPU and intermittently (the receiver and the frequency synthesizer part. This synthesizer part is
In order to receive 380M41z radio waves from a connecting device connected to a wired line and convert them to an intermediate frequency of 22MHz, a local oscillation frequency of 358M41z is generated.

The oscillation frequency output of the synthesizer on the receiver side is radiated into the air as radio waves, albeit slightly. This is especially convenient because the outer case of modern devices is made of plastic molding, so it is not shielded and is easily radiated to the outside.This radio wave is very weak, but The distance is at a level that can be received by other dedicated receivers. Therefore, by receiving this 358 MHz radio wave, you can tell that the cordless phone is nearby and is working. This has the advantage that the location of the cordless phone can be determined accurately.

That is, since the antenna connected to the dedicated receiver can receive signals within several meters from the antenna, it is possible to detect the presence of a cordless telephone in the immediate vicinity of the antenna. In the present invention, it is only necessary to receive the presence of a radio signal or the code within the radio signal, and there is no need to receive an audio signal, so a narrow band receiver is sufficient, so even weak radio waves can be efficiently received. Furthermore, since the receiving frequency is one wave, and an antenna that accurately resonates with the receiving frequency can be used, it is less susceptible to interference from other radio waves and has the advantage of being able to receive efficiently.

Figure 2 shows a receiving device 2 (RX
-1 to RX12) are arranged in large numbers, and is a system for confirming the whereabouts of cordless telephones 3. This cordless telephone 3, shown in FIG. 1, has a set of transmitter and receiver, and can access a public telephone line via a connecting device. From the dedicated receiver, a signal for determining the presence or absence of the cordless telephone 3 is sent to the central control unit (C0) via a connection line 5.
NT). When the control unit C0NT causes the display to be displayed on a display lamp or a CRT, the location of the cordless telephone can be determined with a glance. If only to confirm the presence, a lamp may be lit at the receiver output section to display the information at that location.

On the other hand, a receiving device 4 (R
X-13) is installed at the exit of the room and monitors when cordless telephones are taken out of the room. When the receiving device 4 at the exit of this room confirms the presence of the cordless telephone, it flashes a lamp from the nearby warning display board 6 and sounds a warning sound to warn against unauthorized removal from the room. , helps prevent theft.

Previously, only the location of the phone was checked, but as more cordless phones came into use, it became possible to know which phone was where. By using this identification code to modulate the local oscillation wave of the cordless telephone,
This is easily possible (Figure 1).

Furthermore, there is also a demand for knowing the status of the cordless telephone, such as whether it is in standby mode or in the middle of a call. This becomes possible by processing this request as shown in FIG. The flow at this time is as follows. That is, the device checks whether it is about to make a call or not.If it finds out that it is not in a situation to make a call, it advances the intermittent reception timer of the receiver. When the timer times up, the receiving frequency synthesizer is activated, followed by the receiver, and the device listens to see if its own device is being called by the parent connection device (whether there is an incoming call). If its own device is being called, it sends a call initiation control signal to the frequency synthesizer used in the receiver's local oscillator and modulates it with a self-identification code. The same applies when a key is pressed for the above-mentioned call.

On the other hand, when your own device is not called due to an incoming call,
A control signal consisting of only a self-identification code is simply sent to the synthesizer to modulate the frequency synthesizer. When the 0 call ends, a control signal containing a call end code is sent to the frequency synthesizer and modulated. The dedicated receiver that received these decodes them and sends this signal to the control unit C0NT,
The control unit C0NT can display which equipment is in which location and in what state.

Although the output wave of the frequency synthesizer is modulated in the above example, the purpose can be similarly achieved by encoding the output of the reference frequency oscillator TCXO shown in FIG. This modulation may be done by frequency modulation or the like, but it is also possible to do it by intermittent oscillation output.

Further, although FIG. 1 describes a cordless telephone having two frequency synthesizers, the present invention can be implemented in the same manner for a cordless telephone having only one frequency synthesizer or a crystal oscillation type telephone having no frequency synthesizer.

Although a cordless telephone has been described above, the present invention can be implemented in a similar manner to a mobile telephone with a built-in receiver, a wireless calling device, and the like.

In the present invention, since the standby signal is processed at a time-specific fixed frequency such as a control channel, there is no need to chase the reception channel, and reception is easy, and the system can be simplified.

In Figure 2, we described an integrated antenna and receiver, but only the antenna is placed at each reception location, high-frequency cables are extended from each antenna, and the cables are gathered in the center and the receiver is placed there. It is also possible to do this. Furthermore, instead of having each receiver, there may be only one receiver, and the human power from the antenna may be switched.This configuration allows for a significantly improved and economical design.

In the present invention, an example of indoor use has been described, but it goes without saying that the present invention can be used outdoors as well.

(5) Effects of the Invention As described above, the present invention has a relatively simple and inexpensive configuration, and it is possible to know the location of a cordless telephone, as well as the model number and usage status if necessary, at one center.
Based on this information, it can be effectively used to bill usage fees, improve the efficiency of rental services, prevent theft, etc., and enable smooth operations.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing an example of the structure of a cordless telephone according to the present invention, and FIG. 2 is a system configuration diagram of the present invention.
FIG. 3 is a flowchart for explaining the operating state of the cordless telephone used in the present invention. 2... Receiving device, 3, 4... Cordless telephone,
5... Connection line, C0NT... Control section. 'P12 old

Claims (4)

[Claims] (1) In order to confirm the location of a cordless telephone connected directly or via a private branch exchange or the like to a general wired telephone line network, each cordless telephone is equipped with an antenna to receive leakage radio waves from a local oscillator in the cordless telephone. A plurality of receiving devices including a dedicated receiver are arranged at desired locations within the target area, and the position of the cordless telephone is determined by a control unit having a function of displaying the reception results of the plurality of receiving devices. A location confirmation method for a cordless telephone, characterized in that the cordless telephone is configured to display. (2) The oscillation output wave of the local oscillator in the cordless telephone is modulated by the code indicating the number and usage status of the cordless telephone, so that the control unit can easily determine the usage status of each device of the cordless telephone. A method for confirming the position of a cordless telephone according to claim 1. (3) The cordless telephone position confirmation method according to claim 2, wherein the code includes a code that distinguishes when a call starts and ends when the cordless telephone calls. (4) The oscillation signal of the local oscillator in the cordless telephone is a modulated signal to which a device number, status, etc. are added when the device is on standby, and is completely activated in synchronization with battery saving. A method for confirming the location of a cordless telephone as described in Scope 2.