Radio-telephone system

Claim 3

A method according to claim 1 in which the channel identification signal on the marker channel is transmitted periodically.

Claim 4

A method according to claim 1 or claim 2 in which the mobile station comprises the first of a plurality of such stations, the said channel identification signal identifying a first next available channel and the identity of that channel being stored in a memory element of each of the mobile stations, and wherein the central terminal transmits a second channel identification signal on the marker channel identifying a second next available channel; each mobile station, not otherwise engaged in communication on a communications channel, receiving the second channel identification signal such that the memory elements of each of the mobile stations are updated to identify the second next available channel for subsequent communication between a second mobile station and the central terminal.

Claim 5

A method according to claim 1 or claim 2 in which communication on the next available channel is established by the central terminal transmitting a call signal identifying the mobile station, the mobile station receiving the call signal and transmitting on the next available channel, as'designated by the information stored in its memory element, a guard signal; the central terminal receiving the guard signal and transmitting on the designated next available channel a ring signal; and the mobile station receiving the ring signal.

Claim 6

A method according to claim 4 in which the mobile station comprises a first of a plurality of such stations, and in which communication with a second of the stations is established by the central terminal transmitting a second channel identification signal identifying a second next available channel as assigned by the central terminal; each mobile station, not otherwise in communication on a communication channel, receiving the second channel identification signal and storing in a respective memory element the identity of the second next available channel as specified by a second channel identification signal.

Claim 7

A method according to claim 1 or claim 2 in which communication on the next available channel is established by the mobile station transmitting on the next available channel, as stored in its memory element, a call originate signal, and the central terminal receiving the call originate signal and transmitting a seize signal indicating that the next available channel has been dedicated for communication with the mobile station transmitting the call originate signal.

Claim 8

A method according to claim 6 in which the mobile station comprises the first of a plurality of such stations, and .in which communication between the central terminal and a second of the said stations is established by the central terminal transmitting a second channel identification signal on the marker channel, a second J channel identification signal identifying a second next available channel as assigned by the central terminal for communication between a mobile station and the central terminal, and each mobile station receiving the second channel identification signal and storing in a respective memory element the identity of the second next available channel as specified by the second channel identification signal.

Claim 9

A method according to claim 6 or claim 7 in which communication between the, or the first, mobile station and the central terminal is established by the mobile station receiving the seize signal and transmitting a telephone number signal, and by the central terminal receiving the telephone number signal and dialling the corresponding telephone number to establish contact with a telephone subscriber.

Claim 10

' A method for establishing communication between fixed telephone stations and mobile radio-telephone stations over one of a group of communications channels via a central terminal comprising the steps of: transmitting by the central terminal a plurality of channel identification signals in succession on a marker channel comprising one of said communications channels, each channel identification signal providing an identification of the next available channel as assigned by the central terminal for communication between a mobile radio-telephone station and the central station; scanning said group of communications channels designated for mobile telecommunication by each of said mobile radio-telephone stations to locate a first one of said marker channels by detecting the channel identification signal on such marker channels; storing in a memory element in each of said mobile radio-telephone stations the identity of such next available channel as specified by the channel identification signal detected; communicating between one of said mobile radio-telephone stations and its central terminal on said next available channel; and repeatedly scanning and storing by each remaining mobile radio-telephone station to effect communication between any such mobile radio-telephone station and said central terminal on a respective next available channel.

Claim 11

' A method for establishing communication between fixed telephone stations and mobile radio-telephone stations over one of a group of communications channels via a central terminal comprising the steps of: transmitting by the central terminal a plurality of channel identification signals in succession on a marker channel comprising one of said communications channels, each channel identification signal providing an identification of the next available channel as assigned by the central terminal for communication between a mobile radio-telephone station and the central station; scanning said group of communications channels designated for mobile telecommunication by each of said mobile radio-telephone stations to locate a first one of said marker channels by detecting the channel identification signal on such marker channels; storing in a memory element in each of said mobile radio-telephone stations the identity of such next available channel as specified by the channel identification signal detected; communicating between one of said mobile radio-telephone stations and its central terminal on said next available channel; and repeatedly scanning and storing by each remaining mobile radio-telephone station to effect communication between any such mobile radio-telephone station and said central terminal on a respective next available channel.

Claim 12

A method according to claim 9 in which the central terminal transmits the next channel identification signal in each succession in response to each communication effected between each mobile radio-telephone station and the central terminal on a respective next available channel.

Claim 13

ll. A method for establishing voice communication between first and second stations over one of a group of communications channels via a central terminal comprising the steps of: transmitting by the central terminal a plurality of channel identification signals in succession on a marker channel comprising one of said communications channels, each channel identification signal providing an identification of the next available channel assigned by the central terminal for communication between a first station and the central station; scanning said group of communications channels designated for communication by each of said first stations to locate a first one of said marker channels by detecting the channel identification signal on such marker channels; storing in a memory element in each of said first stations the identity of such next available channel as specified by the channel identification signal detected; communicating between one of said first stations and its central terminal on said next' available channel; and repeatedly scanning and storing by each remaining first station to effect voice communication between any such first station and said central terminal on a respective next available channel.

Claim 14

ll. A method for establishing voice communication between first and second stations over one of a group of communications channels via a central terminal comprising the steps of: transmitting by the central terminal a plurality of channel identification signals in succession on a marker channel comprising one of said communications channels, each channel identification signal providing an identification of the next available channel assigned by the central terminal for communication between a first station and the central station; scanning said group of communications channels designated for communication by each of said first stations to locate a first one of said marker channels by detecting the channel identification signal on such marker channels; storing in a memory element in each of said first stations the identity of such next available channel as specified by the channel identification signal detected; communicating between one of said first stations and its central terminal on said next' available channel; and repeatedly scanning and storing by each remaining first station to effect voice communication between any such first station and said central terminal on a respective next available channel.

Claim 15

A method according to claim 11 in which the central terminal transmits the next channel identification signal in each succession in response to each communication effected between each first station and the central terminal on a respective next available channel.

Claim 16

Apparatus for establishing communication between a central terminal of a radio-telephone system and a mobile radio-telephone station over one of a group of communications channels the apparatus comprising: means located at the central terminal for transmitting a channel identification signal on one of the communications channels designated as a marker channel, the channel identification signal providing an identification of the next available channel as assigned by the central terminal for communication between a mobile radio-telephone station and the central terminal; and means located at the mobile station for scanning the communications channels to locate the marker channel by detecting the channel identification signal transmitted thereon, and for storing the identity of the next available channel as specified by the channel identification signal detected by the scanning means.

Claim 17

Apparatus for establishing communication between a central terminal of a radio-telephone system and a mobile radio-telephone station over one of a group of communications channels the apparatus comprising: means located at the central terminal for transmitting a channel identification signal on one of the communications channels designated as a marker channel, the channel identification signal providing an identification of the next available channel as assigned by the central terminal for communication between a mobile radio-telephone station and the central terminal; and means located at the mobile station for scanning the communications channels to locate the marker channel by detecting the channel identification signal transmitted thereon, and for storing the identity of the next available channel as specified by the channel identification signal detected by the scanning means.

Claim 18

An apparatus according to claim 13 wherein the channel identification signal is a periodic signal.

Claim 19

An apparatus according to claim 13 or 14 wherein the channel identification signal is a digital signal.

Claim 20

An apparatus according to claim 13 or 14 wherein the channel identification signal is a tone.

Claim 21

Apparatus according to any one of the claims 13 to 16 in which the mobile station is one of a plurality of such stations, the channel identification signal identifying a first next available channel and each mobile station storing the identity of the first next available channel, and the apparatus further comprising means located at the central terminal for transmitting on the marker channel a second channel identification signal identifying a second next available channel, and means located at each mobile station not otherwise in communication on one of the communications channels for receiving the second marker signal and for updating the respective stores to identify the second next available channel.

Claim 22

Apparatus according to any one of the claims 13 to 16 further comprising means located at the central terminal for transmitting the call signal identifying the mobile station, means located at the mobile station for receiving the call signal and for transmitting on the next available channel, as designated by the stored information at the station, a guard tone; means located at the central terminal for receiving the guard tone and for transmitting in response thereto a ring signal, and means located at the mobile station for receiving the ring signal.

Claim 23

Apparatus according to claim 17 further comprising means located at the central terminal for transmitting a call signal identifying a first of the mobile stations, means located at the first mobile station for receiving the call signal and for transmitting in response thereto on the next available channel, as designated by the information stored at the station, a guard tone; means located at the central terminal for receiving the guard signal and for transmitting in response thereto on the first next available channel a ring signal,. and means located at the first mobile station for receiving the ring signal.

Claim 24

Apparatus according to any one of the claims 13 to 16 further comprising means located at the mobile station for transmitting on. the next available channel, as stored at the station, a call originate signal, and means located at the central terminal for receiving the call originate signal and for transmitting in response thereto a seize signal indicating that the next available channel has been dedicated for communication with the mobile station transmitting the call originate signal.

Claim 25

Apparatus according to claim 17 further comprising means located at a first of the mobile stations for transmitting on the first next available channel, as stored at the station, a call originate signal, and means located at the central terminal for receiving the call originate signal and for transmitting in response thereto a seize signal indicating that the first next available channel has been dedicated for communication with the first mobile station transmitting the call originate signal whereby communication between the first mobile station and the central terminal is established on the dedicated communications channel and communication between a second mobile station and the central terminal is established on the second next available channel.

Claim 26

Apparatus for establishing communication between a central.terminal of a communication system and first stations over one of a group of communications channels comprising: means located at the central terminal for transmitting a first channel identification signal on one of the communications channels designated as a marker channel, the first channel identification signal including an identification of a first next available channel as assigned by the central terminal for communication between a first station and the central terminal; means located at each of the first stations for scanning the communications channels to locate the marker channel by detecting the first channel identification signal on the marker channel and for storing in a memory element the identity of the first next available channel as specified by the channel identification signal detected;-means located at one of said first stations for transmitting on the first next available channel,as stored in its memory element, a call originate signal; means located at the central terminal for receiving the call originate signal and transmitting in response thereto a seize signal indicating that the first next available channel has been dedicated for communication with the said one of the first stations transmitting the call originate signal; means for establishing communication between the said one of the first stations and the central terminal on the dedicated communications channel; further means located at the central terminal for transmitting a second channel identification signal on the marker channel, the second channel identification signal identifying a second next available channel as assigned by the central terminal for communication between another first station and the central terminal; said first stations having means for releasing the second channel identification signal; further means located at each of the first stations for storing the identity of the second next available channel as specified by the second channel identification signal; and means for establishing communication between said another first station and the central terminal on the second next available channel.

Claim 27

Apparatus for establishing communication between a central.terminal of a communication system and first stations over one of a group of communications channels comprising: means located at the central terminal for transmitting a first channel identification signal on one of the communications channels designated as a marker channel, the first channel identification signal including an identification of a first next available channel as assigned by the central terminal for communication between a first station and the central terminal; means located at each of the first stations for scanning the communications channels to locate the marker channel by detecting the first channel identification signal on the marker channel and for storing in a memory element the identity of the first next available channel as specified by the channel identification signal detected;-means located at one of said first stations for transmitting on the first next available channel,as stored in its memory element, a call originate signal; means located at the central terminal for receiving the call originate signal and transmitting in response thereto a seize signal indicating that the first next available channel has been dedicated for communication with the said one of the first stations transmitting the call originate signal; means for establishing communication between the said one of the first stations and the central terminal on the dedicated communications channel; further means located at the central terminal for transmitting a second channel identification signal on the marker channel, the second channel identification signal identifying a second next available channel as assigned by the central terminal for communication between another first station and the central terminal; said first stations having means for releasing the second channel identification signal; further means located at each of the first stations for storing the identity of the second next available channel as specified by the second channel identification signal; and means for establishing communication between said another first station and the central terminal on the second next available channel.