Trunked radio repeater system

Apparatus for achieving reliable and prompt communication within a trunked radio repeater system having a digital control channel and plural working channels, which working channels are assigned for temporary use of individual radio units specified by digital control signals transmitted over the control channel, said control channel carrying inbound digital control signals from said radio units to a control site, said inbound digital control signals having a time-multiplexed format defining discrete signalling slots, said apparatus comprising:

• (a) means for requesting assignment of a working channel by passing digital request signals over a control channel inbound signalling slot;
• (b) means for monitoring said control channel for responsive channel assignment signals returned over the control channel within a predetermined expected response time;
• (c) means for repeating said request and monitoring functions within a retry time window if there is no detection of such responsive channel assignment signals;
• and
• (d) means connected to said repeating means for increasing the duration of said retry time window as a function of the number of retries.

A method for achieving reliable and prompt communication within a trunked radio repeater system having a digital control channel and plural working channels, which working channels are assigned for temporary use by individual radio units specified by digital control signals on the control channel, said method comprising the steps of:

• detecting, by testing control signals provided on at least one of said control channel or assigned working channel at each radio unit involved in a communique, a trunked status signal identifying whether the then assigned usage of the working channel is to be transmission or message trunked;
• immediately reverting operation of a calling unit to the control channel upon PTT release if transmission-trunked status has been detected;
• and
• preventing transmissions from a called unit on the assigned working channel if transmission-trunked status has been detected.

Apparatus for achieving reliable and prompt communication within a trunked radio repeater system having a digital control channel and plural working channels, which working channels are assigned for temporary use by individual radio units specified by digital control signals on the control channel, said apparatus comprising:

• means for testing a trunked status signal within control signals provided on at least one of said control channel or assigned working channel at each radio unit involved in a communique;
• means connected to said testing means for determining in response to said testing whether the then assigned usage of the working channel is to be transmission or message trunked;
• means for immediately reverting operation of a calling unit to the control channel upon PTT release if transmission-trunked status has been detected;
• and
• means for preventing transmissions from a called unit on the assigned working channel if transmission-trunked status has been detected.

Apparatus for achieving reliable and prompt communication within a trunked radio repeater system having a digital control channel and plural working channels, which working channels are assigned for temporary use of individual radio units specified by digital control signals on the control channel, said apparatus comprising:

• means for monitoring said control channel for a working channel assignment for a communique initiated by a calling radio unit;
• means for recording the identity of the calling radio unit within a called radio unit;
• and
• means for subsequently automatically initiating a channel assignment call request from the just-called radio unit back to the earlier said calling radio unit using said recorded identity of the earlier said calling radio unit if a PTT switch of the just-called radio is actuated within a predetermined time period after cessation of the just earlier communique.

A method for achieving reliable and prompt communication within a trunked radio repeater system having a digital control channel and plural working channels, which working channels are assigned for temporary use by individual radio units specified by digital control signals on the control channel, said method comprising the steps of:

• monitoring the control channel for working channel assignments addressed to a predetermined radio unit;
• shifting said radio unit's operation to an assigned working channel in response to detection of such assignment on the control channel;
• and
• initially, upon arrival on the assigned working channel, simultaneously monitoring that working channel for an extended dotting signal and for confirmation signals confirming the assignment of that particular channel to said radio unit for a communique.

Apparatus for achieving reliable and prompt communication within a trunked radio repeater system having a digital control channel and plural working channels, which working channels are assigned for temporary use by individual radio units specified by digital control signals on the control channel, said apparatus comprising:

• means for monitoring the control channel for working channel assignments addressed to a predetermined radio unit;
• means for shifting said radio unit's operation to an assigned working channel in response to detection of such assignment on the control channel;
• and
• means for simultaneously monitoring the assigned working channel initially upon arrival thereat for a dotting signal of extended duration and for confirmation signals confirming the assignment of that particular channel to said radio unit for a communique.

A method for achieving reliable and prompt communication within a trunked radio repeater system having a digital control channel and plural working channels, which working channels are assigned for temporary use of individual radio units specified by digital control signals on the control channel, said method comprising the steps of:

• requesting assignment of a working channel by passing digital request signals from a first radio unit to a control site over said control channel;
• assigning a specific working channel to said first radio unit and to at least one second radio unit by passing digital assignment signals over said control channel;
• exchanging digital handshake signals over said assigned working channel between said control site and at least one of said radio units;
• and
• releasing said units for communication over said assigned working channel by sending digital release signals on said assigned working channel in response to successful exchange of said handshake signals.

A method for achieving reliable and prompt communication within a trunked radio repeater system having a digital control channel and plural working channels, which working channels are assigned for temporary use of individual radio units specified by digital control signals on the control channel, said method comprising the steps of:

• requesting assignment of a working channel by passing digital request signals from a first radio unit to a control site over said control channel;
• assigning a specific working channel to said first radio unit and to at least one second radio unit by passing digital assignment signals from said control site to said radio units over said control channel;
• confirming said assignment by sending digital confirmation signals on said assigned working channel from said control site;
• achknowledging successful receipt of said assignment and confirmation signals by at least one of said units, including sending digital acknowledgement signals from said at least one unit to said control site over said assigned working channel in response to said confirmation signals;
• and
• releasing at least one of said units for communication by sending digital release signals over said assigned working channel in response to said acknowledgement signals.

A system of apparatus for achieving reliable and prompt communication within a trunked radio repeater system having a digital control channel and plural working channels, which working channels are assigned for temporary use of individual radio units specified by digital control signals on the control channel, said system comprising:

• means for requesting assignment of a working channel by passing digital request signals from a first radio unit to a control site over said control channel;
• means for assigning a specific working channel to said first radio unit and to at least one second radio unit by passing digital assignment signals over said control channel;
• means for exchanging digital handshake signals over said assigned working channel between said control site and at least one of said radio units;
• and
• means for releasing said units for communication over said assigned working channel by sending digital release signals on said assigned working channel in response to successful exchange of said handshake signals.

A system for achieving reliable and prompt communication within a trunked radio repeater system having a digital control channel and plural working channels, which working channels are assigned for temporary use of individual radio units specified by digital control signals on the control channel, said system comprising:

• means for requesting assignment of a working channel by passing digital request signals from a first radio unit to a control site over said control channel;
• means for assigning a specific working channel to said first radio unit and to at least one second radio unit by passing digital assignment signals from said control site to said radio units over said control channel;
• means for confirming said assignment by sending digital confirmation signals on said assigned working channel from said control site;
• means for acknowledging successful receipt of said assignment and confirmation signals by at least one of said units, including means for sending digital acknowledgement signals from said at least one unit to said control site over said assigned working channel in response to said confirmation signals;
• and
• means for releasing at least one of said units for communication by sending digital release signals over said assigned working channel in response to said acknowledgement signals.

A method for achieving reliable and prompt communication within a trunked radio repeater system having a digital control channel and plural working channels, which working channels are assigned for temporary use of individual radio units specified by digital control signals on the control channel, said method comprising the steps of:

• requesting assignment of a working channel;
• monitoring for digital working channel assignment signals over said control channel issued in response to said requested assignment;
• exchanging digital handshake signals over said assigned working channel between said control site and said radio units;
• and
• releasing said assigned working channel for communication over by sending digital release signals on said assigned working channel in response to successful exchange of said handshake signals.

A system of apparatus for achieving reliable and prompt communication within a trunked radio repeater system having a digital control channel and plural working channels, which working channels are assigned for temporary use of individual radio units specified by digital control signals on the control channel, said system comprising:

• means for requesting assignment of a working channel;
• means for assigning a specific working channel to radio unit by passing digital assignment signals over said control channel;
• means for exchanging digital handshake signals over said assigned working channel between said control site and at least one of said radio units;
• and
• means for releasing said assigned working channel for communication thereover by sending digital release signals on said assigned working channel in response to successful exchange of said handshake signals.

A radio unit for achieving reliable and prompt communication within a trunked radio repeater system having a digital control channel and plural working channels, which working channels are assigned for temporary use of individual radio units specified by digital control signals on the control channel, said radio unit comprising:

• means for requesting assignment of a working channel by passing digital request signals to a control site over said control channel;
• means for detecting digital working channel assignment signals over said control channel;
• means for exchanging digital handshake signals with said control site over said assigned working channel, and
• means for detecting digital release signals on said assigned working channel after successful exchange of said handshake signals and for unmuting communication over the assigned working channel in response to said detected release signals.