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An apparatus for controlling hand-off in a spread-spectrum-CDMA-communications system, for radio devices moving from one cell to another, with each cell having a base station transmitting spread spectrum signals with generic-chip-code signals. A radio device includes a cellular antenna, matched filt

An apparatus for controlling hand-off in a spread-spectrum-CDMA-communications system, for radio devices moving from one cell to another, with each cell having a base station transmitting spread spectrum signals with generic-chip-code signals. A radio device includes a cellular antenna, matched filters, and detectors for detecting generic-chip-code signals embedded in spread-spectrum-communications signals. A comparator generates a comparison signal by comparing the relative time of arrival of a second detected signal with a first detected signal. A receiver-message-chip-code generator generates a replica of the message-chip-code signal, and a message mixer despreads the spread-spectrum-communications signal. A synchronization circuit synchronizes the receiver-message-chip-code generator to the first generic-chip-code signal for receiving the first spread-spectrum-communications signal or to the second generic-chip-code signal for receiving the second spread-spectrum communications signal, depending on a threshold. A control unit switches transmitting the message data, embedded in the first spread-spectrum-communications signal from the first base station, to the second spread-spectrum-communications signal transmitted from the second base station. Hand-off from an analog base station to a second base station utilizing spread spectrum is also possible.

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An apparatus for controlling hand-off of radio devices moving from one cell toward an adjacent cell of a spread-spectrum code-division-multiple-access communications system (spread-spectrum-CDMA-communications system), each adjacent cell having its own generic-chip-code signal embedded in a spread-s

An apparatus for controlling hand-off of radio devices moving from one cell toward an adjacent cell of a spread-spectrum code-division-multiple-access communications system (spread-spectrum-CDMA-communications system), each adjacent cell having its own generic-chip-code signal embedded in a spread-spectrum-communications signal, comprising: a first base station for transmitting a first spread-spectrum-communications signal having a first generic-chip-code signal and message data spread-spectrum processed with a message-chip-code signal, embedded therein; a second base station for transmitting a second spread-spectrum communications signal having a second generic-chip-code signal embedded therein; a radio device including, a cellular antenna; a first matched filter coupled to said cellular antenna and having a first impulse response matched to the first generic-chip-code signal; a first detector coupled to said first matched filter for detecting the first generic-chip-code signal embedded in the first spread-spectrum-communications signal communicated from said first-base station and outputting a first detected signal; a second matched filter coupled to said cellular antenna and having a second impulse response matched to the second generic-chip-code signal; a second detector coupled to said second matched filter for detecting the second generic-chip-code signal embedded in the second spread-spectrum-communications signal communicated from said second base-station and outputting a second detected signal; a comparator coupled to said first detector and to said second detector for generating a relative time comparison signal by comparing time of detecting the second detected signal with time of detecting the first detected signal; a receiver-message-chip-code generator for generating a replica of the message-chip-code signal; a message mixer coupled to said receiver-message-chip-code generator and said cellular antenna, responsive to the replica of the message-chip-code signal, for despreading one of the first spread-spectrum-communications signal and the second spread-spectrum-communications signal as a modulated-data signal; a message-bandpass filter coupled to said message mixer for filtering the modulated-data signal; a message detector for demodulating the modulated-data signal as received data; a synchronization circuit coupled to said comparator and responsive to the relative time comparison signal being greater than a threshold, for synchronizing said receiver-message-chip-code generator to the first generic-chip-code signal for receiving the first spread-spectrum-communications signal from said first base station, and responsive to the relative time comparison signal being less than the threshold, for synchronizing said receiver-message-chip-code generator to the second generic-chip-code signal for receiving the second spread-spectrum-communications signal from said second base station; and a control unit coupled to said first base station and said second base station and to a plurality of other base stations for switching the message data spread-spectrum processed with the message-chip-code signal, embedded in the first spread-spectrum-communications signal transmitted from said first-base station, to the second spread-spectrum-communications signal transmitted from said second base station.