Motorola Corporation

Motorola Mobility LLC

Gregory Peter Spock

Xiaoyong Yu

Method and system for synchronizing a receiver in an Orthogonal Frequency Division Multiplexing (OFDM) system. The method comprises transforming () a received signal from the time domain into the frequency domain to produce a transformed signal. The method further comprises rotating () each set of ranging tones of the transformed signal in the frequency domain based on a corresponding tone index to produce a set of phase-rotated frequency domain received ranging tones that is equivalent to time domain shifted ranging signals. Each ranging tone is rotated iteratively over a predefined set of delay-values and each delay-value within the predefined set of delay-values ranges from zero to a predetermined time delay. Also, the method comprises computing () a detection metric corresponding to each delay-value within the predefined set of delay-values based on the set of phase-rotated frequency domain received ranging tones.

Method and system for synchoronizing a receiver in an OFDM system

In a code division multiple access (CDMA) signal demodulator in a communication system (50), samples of a CDMA signal are stored in a sample buffer (52). A plurality of the samples that represent a plurality of chips of a symbol are then recalled from the sample buffer (52). Thereafter, the plurality of samples are demodulated in parallel (56) using a selected user code (68) to produce at least a portion of a user's symbol in the code division multiple access signal. Signals from multiple users (22, 24) having multiple fingers are demodulated by sharing the resources of a parallel demodulator (56). Signal searching may use the same parallel demodulator (56). Fingers for multiple users may be dynamically allocated and reallocated according to the needs of each user's signal and the total demodulation resources available.

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Fort Worth, TX, United States of America

Gregory Peter Spock