Patent ID: 6091703
Filing Date: 2000-07-18
Classification: H04B,H04L

Abstract:
A user terminal adapted for spread-spectrum transmission of data channels in a bulk decodable uplink channel, said user terminal comprising:a downlink demodulator for producing a demodulated received signal and for extracting a downlink symbol clock from said demodulated received signal;error correction circuitry connected to said downlink demodulator for extracting a synchronization word from said demodulated received signal and for producing a corrected received signal, said synchronization word provided to a plurality of additional terminals transmitting in said uplink channel;a data demultiplexer connected to said error correction circuitry for extracting timing correction information from said corrected received signal;a timing controller outputting a system clock providing code word alignment of a data channel to be transmitted by said user terminal with code words to be transmitted by said additional terminals, said system clock based on said downlink symbol clock, said synchronization word, and said timing correction information;a spread-spectrum spreader for encoding user data into said data channel; anda transmitter connected to said spread-spectrum spreader for transmitting said data channel in said uplink channel of an uplink beam to a satellite.