Method and apparatus for delivering messages to portable communication units in a radio communication system

A portable communication unit having a radio frequency (RF) receiver and an RF transmitter for transmitting an acknowledge back signal, and operating within a radio communication system comprising a plurality of communication cells and a paging terminal, and wherein each of the communication cells comprises one or more transmitters for transmitting an information signal intended for reception by said the portable communication unit, said portable communication unit comprising:

• demodulator means coupled to the RF receiver for demodulating said information signal, wherein said information signal includes a color code word which identifies a subset of the plurality of communication cells for which radio coverage does not overlap, and further includes one or more induced errors;
• sync correlator means coupled to said demodulator means for decoding one of a predetermined set of color code words of an error correcting code set from said information signal;
• reporter means coupled to said sync correlator means and said RF transmitter for generating said acknowledge back signal which includes a reported color code value determined from said one of said predetermined set of color code words and
• wherein said information signal comprises a bit synchronization code and an information message, and said color code word is within a first portion of the bit synchronization code, and wherein said sync correlation means comprises:
• color code word pattern generator means for generating said predetermined set of color code words;
• and
• color code decoder means coupled to said color code word pattern generator means and to said sync correlator means for matching said first portion of the bit synchronization code to a color code word of said predetermined set of color code words to determine a number of bits which mismatch and assigning, as said reported color code value, one of a plurality of pre-determined valid color code values associated one for one with the color code words of said predetermined set of color code words when the number of bits which mismatch is less than a predetermined number.

A method of delivering messages to a plurality of portable communication units, wherein each of said plurality of portable communication units has a receiver for receiving information signals and a transmitter for transmitting acknowledge back signals and operates within a radio communication system comprising a plurality of communication cells and a paging terminal having a subscriber data base within which cell locations are associated one to one with each of the plurality of portable communication units, wherein each of the communication cells comprises one or more transmitters coupled to the paging terminal for transmitting said information signals intended for reception by said plurality of portable communication units, and wherein each of the communication cells further comprises one or more fixed receivers coupled to the paging terminal for receiving the acknowledge back signals and communicating the acknowledge back signals to the paging terminal, said method comprising the steps of:

• transmitting, to a portable communication unit from one of the plurality of communication cell transmitters, an information signal which includes a predetermined color code word which identifies a subset of the plurality of communication cells for which radio coverage does not overlap;
• receiving at a fixed receiver an acknowledge back signal transmitted from said portable communication unit in response to said information signal received by said portable communication unit, said acknowledge back signal comprising a reported color code value determined from said predetermined color code word;
• communicating said acknowledge back signal from the fixed receiver to the paging terminal;
• and
• analyzing said reported color code value in the paging terminal to determine a cell location of the portable communication unit,
• assigning to said portable communication unit within the subscriber data base of the paging terminal, said cell location which is identified in said analyzing step;
• identifying a plurality of differing information signals intended for portable communication units in cells having cell locations not necessarily the same and having a common color code assigned within said subscriber data base;
• and
• simultaneously transmitting said plurality of differing information signals from the transmitters of cells having cell locations identified in said identifying step.

A method of locating a portable communication unit having a receiver for receiving an information signal and a transmitter for transmitting an acknowledge back signal, said portable communication unit operating within a radio communication system comprising a plurality of communication cells and a paging terminal, wherein each of the communication cells comprises one or more transmitters coupled to the paging terminal for transmitting said information signal, and wherein each of the communication cells further comprises one or more fixed receivers coupled to the paging terminal for receiving the acknowledge back signal and communicating the acknowledge back signal to the paging terminal, wherein said information signal comprises a bit synchronization code and an information message, the method comprising the steps of:

• transmitting, to said portable communication unit from one of the plurality of communication cell transmitters, said information signal which includes a color code word within a first portion of the bit synchronization code, wherein said color code word identifies a subset of the plurality of communication cells for which radio coverage does not overlap;
• receiving said information signal and one or more induced errors at said portable communication unit;
• decoding, in said portable communication unit, said color code word from said information signal and the one or more induced errors, said step of decoding further comprising the steps of:
• matching said first portion of the bit synchronization code containing said color code word to one color code word of a set of predetermined color code words to determine a number of bits which mismatch;
• and
• assigning, as a reported color code value, one of a plurality of predetermined valid color code values associated one for one with said set of predetermined color code words when the number of bits which mismatch is less than a predetermined number of bits in said matching step;
• transmitting from said portable communication unit said acknowledge back signal including said reported color code value determined from said color code word;
• receiving at a fixed receiver said acknowledge back signal;
• communicating said acknowledge back signal from the fixed receiver to the paging terminal;
• and
• analyzing, in the paging terminal, said reported color code value to determine a cell location of the portable communication unit.

In a portable communication unit having a receiver for receiving information signals and a transmitter for transmitting acknowledge back signals, and operating within a radio communication system comprising a plurality of communication cells and a paging terminal, wherein each of the communication cells comprises one or more transmitters for transmitting an information signal intended for reception by said portable communication unit, a method of identifying a subset of the plurality of communication cells for which radio coverage does not overlap, wherein said information signal includes a color code word which identifies said subset, and wherein said information signal comprises a bit synchronization code and an information message, and said color code word is within a first portion of the bit synchronization code, the method comprising the steps of:

• receiving at said portable communication unit said information signal and one or more induced errors;
• decoding said color code word from said information signal and the one or more induced errors, said step of decoding further comprising the steps of:
• matching said first portion of the bit synchronization code to one color code word of a predetermined set of color code words to determine a number of bits which mismatch;
• and
• assigning, as a reported color code value, one of a plurality of pre-determined valid color code values associated one for one with the color code words of said predetermined color code words when the number of bits which mismatch is less than a predetermined number;
• and
• transmitting from said portable communication unit, for communication to said paging terminal, an acknowledge back signal comprising said reported color code value determined from said color code word decoded in said decoding step.