Public safety communications network using asymmetric receive/transmit channels

A public safety communications network using asymmetric channels for receiving requests for data from a mobile client and delivering data to the mobile client, said network comprising:

• a land mobile radio system (LMRS) for providing a narrowband channel for requesting the data;
• a terrestrially broadcast high definition DTV station transmitter for providing a wideband channel for delivering the requested data over the wideband channel;
• and
• a forward error correction (FEC) regulation system for use in transmitting requested data to the mobile client wherein FEC strength is regulated as a function of historical channel performance statistics for a geographical location.

A public safety communications network using asymmetric channels for receiving requests for data from a mobile client and delivering data to the mobile client, said network comprising:

• a land mobile radio system (LMRS) for providing a narrowband channel for requesting the data;
• terrestrially broadcast high definition DTV station transmitter for providing a wideband channel for delivering the requested data over the wideband channel, said terrestrially broadcast high definition DTV station transmitter configured for inserting the requested data into a DTV signal with a data multiplex insertion system and for transmitting the DTV signal;
• a DTV datacast receiver located with the mobile client for receiving the requested data from the terrestrially broadcast high definition DTV station transmitter;
• wherein the public safety communications network has an addressing system for identifying unique mobile client addresses and unique mobile client group addresses and to select a terrestrially broadcast high definition DTV station transmitter for delivering response messages to a unique mobile client and a unique mobile client group in accordance with the address;
• and
• wherein the terrestrially broadcast high definition DTV station transmitter is selected by using mobile client position determined from a GPS receiver and transmitted with the request for data and the terrestrially broadcast high definition DTV station transmitter transmits messages to said unique mobile client with forward error correction which is regulated as a function of geographic location of said unique mobile client.

A public safety communication system comprising:

• a public safety communication center;
• a first public safety vehicle with a two-way radio therein configured for providing wireless voice communication with a second public safety vehicle;
• a global positioning system (GPS) receiver disposed on said first public safety vehicle and configured for determining a location of the first public safety vehicle;
• a television station configured to terrestrially broadcast, to television consumers with digital television receivers, high definition digital television programming using a digital television transmitter;
• a first digital television datacast receiver disposed in said first public safety vehicle, and configured to receive data downloads via a signal broadcast from said digital television transmitter;
• a second digital television datacast receiver disposed in said second public safety vehicle and configured to receive data downloads via a signal broadcast from said digital television transmitter;
• a first information output device disposed in said first public safety vehicle;
• a second information output device disposed in said second public safety vehicle;
• means for permitting said public safety communication center to broadcast an emergency graphical message to said first public safety vehicle directly, via said digital television transmitter and output a graphical message on said first information output device, without causing said graphical message to be displayed on television sets of said television consumers;
• and
• means for altering a broadcast from said digital television transmitter in response to information from said GPS receiver so as to improve reception capabilities of graphical images at the location of said first public safety vehicle;
• wherein said means for altering a broadcast utilizes a forward error correction (FEC) regulation system for use in transmitting said graphical message to the first digital television datacast receiver disposed in said first public safety vehicle wherein FEC strength is regulated as a function of historical channel performance statistics for a geographical location.