摘要:
In a cordless key telephone system in which radio-frequency connections are established between exchange lines and cordless stations in response to a call request, a ringing signal is transmitted in response to an incoming call by containing in it the identification of the line at which the call is terminated. Each cordless station has an array of line keys associated respectively with the exchange lines and an array of line indicators associated respectively with the line keys, and a memory for storing tenant data indicating the lines to which the cordless station is authorized to access. The cordless station examines the tenant data in response to receipt of the ringing signal, and activates one of the line indicators if the indicated line is found in the tenant data, or examines the tenant data in response to an outgoing call originated from the cordless station operating a line key, and allows a connection to be established from that station to an exchange line when the line associated with the operated line key is found in the tenant data.
摘要:
In a cordless key telephone system, access units are located in groups corresponding to service areas for broadcasting radio signals on a control channel or on an assigned speech channel to cordless stations. A main controller selects one of the access units for each service area in response to an incoming call from the switched telephone network and sends a first alert signal to the selected access units to cause them to broadcast a recurrent sequence of second alert signals containing the identifiers of standby cordless stations. The second alert signal is received by each standby cordless station and an ACK signal is transmitted if the received signal contains its identifier. The ACK signal is copied by each access unit for transmission to the main controller, whereupon it returns a proceed-to-assign signal if the number of the received copies of the ACK signals is equal to the number of all standby stations. The proceed-to-assign signal is received by the selected access units and a channel assignment signal is broadcast indicating the assigned channel. On receiving it, each station is switched to the assigned channel and one of the stations in each area transmits an end-of-switching signal to cause the access units to broadcast ringing signals containing the identifiers of the alerted stations. In response to a given cordless station going off hook, an off-hook signal is sent from it and copied by the associated access unit for transmission to the main controller, which returns a turn-on signal to allow the given station to activate its speech circuit.
摘要:
A new cordless telephone is registered to an existing cordless telephone system by transmitting the product identification number of the new cordless telephone from the access unit of the system to the new cordless telephone, receiving the transmitted product identification number at the new cordless telephone and verifying that the transmitted product identification number is correctly received. In response to the verification, the system and telephone identification numbers of the new cordless telephone are transmitted from the access unit to the new cordless telephone and stored into an electrically erasable programmable read-only memory of this telephone to be used for establishing calls.
摘要:
An interconnection control method in a cordless telephone system having a connection unit connected to a subscriber line and a plurality of radio telephone sets connected through a radio communication circuit to the connection unit. Each of the radio telephone sets in a signal transmits, in a signal transmission mode, a calling signal containing group identification information and individual identification information. The connection unit, only when the received group identification information coincides with a predetermined content, returns a calling answer signal containing group identification information and individual identification information of the transmitting radio telephone sets and then establishes a speech channel between the connection unit and the other party telephone set.
摘要:
A radio communication system of a multi-channel access type in which an idle one of a plurality of radio channels is detected to perform transmission and reception of voice signals, data signals or the like. In the present system, in the case where a base unit receives an incoming call from a wired line, the base unit transmits to a plurality of radio terminal units a speech channel designation signal as well as a representative radio terminal designation signal specifying a representative radio terminal unit from the plurality of radio terminal units, and when receiving a channel switching completion signal from the representative radio terminal unit, the base unit transmits a signal for generation of ringing tones to the plurality of radio terminal units at the same time to cause the plurality of radio terminal units to generate the ringing tones at the same time.
摘要:
Disclosed is a radio channel control method for a system including a main apparatus connected to a telephone line and having a channel control function, a plurality of stationary apparatuses connected to the main apparatus and each having a radio transmitter/receiver, and a portable telephone capable of communicating with the stationary apparatuses through a radio channel. In this method, the main apparatus designates each stationary apparatus in a main or sub state to control communication with the portable telephone and monitors a state signal including information of the main or sub state transmitted from each stationary apparatus. When the state signal from a given stationary apparatus does not coincide with a state of the given stationary apparatus designated by the main apparatus, the main apparatus transmits a state designation signal to the given stationary apparatus to coincide with the state designated by the main apparatus.
摘要:
A radio telephone having a base unit connected to a wired telephone line, a handset unit connectable to the base unit over a radio channel and provided with a hook switch, and a charger for selectively charging the handset unit. The handset unit is automatically controlled to either an on-hook state or an off-hook state when removed from the charger, depending upon the hook state in which the handset unit has been held before the start of charging.
摘要:
In a cordless key telephone system where adjacent service zones having the same control channel are overlapped, forming an unavoidable interference-affected overlapping zone, a main unit initially selects an access unit from each service zone in response to an incoming call from a network and transmits a first alert signal to that unit where it is broadcast to elicit an acknowledgement (ACK) signal from cordless stations. On receiving it, the access unit selects a speech channel, broadcasts a first channel assignment signal on the control channel, and then a first ringing signal on the selected speech channel. The main unit determines whether there is a cordless station falling to respond to the first alert signal. If such a station exists, the main unit selects a first, idle access unit which is located in one of the adjacent service zones. A second alert signal is then broadcast on a control channel from the first access unit. Following receipt of an ACK signal from a cordless station, a second channel assignment signal is broadcast from the first access unit, signalling the identification of a speech channel previously selected by a second, initially selected access unit located in the adjacent service zones. A second ringing signal is broadcast from the second access unit on the previously selected speech channel.
摘要:
A device for recovering a clock from received data which has a different duty ratio is disclosed. The optimum timing of a recovered clock is determined based on the pulse width of received data. A clock is accurately recovered so long as the duty ratio of received data is not greater than .+-.50%.
摘要:
Where a carrier wave is received from a called radio telephone set and where the identification signal of the radio telephone set coincides with a preassigned identification signal, transmission of a paging signal from a base unit is stopped. Even when the identification signals do not coincide with each other, the paging signal is sent continuously over a definite interval. Communication is established only when the signal from a handset to the base station has a predetermined strength and a proper I.D.