Abstract: An apparatus (300) for and method of synchronizing OFDM signals utilizes a single baud to provide synchronization in time, frequency, and per-subcarrier rotation (201). Timing and fractional subcarrier frequency synchronization may be obtained from either a known or unknown (e.g., data symbol) baud having known symmetry properties. Because all three synchronization tasks may be accomplished utilizing a single sync baud, the present invention is spectrally efficient. A differential correlation metric is utilized to efficiently provide integer subcarrier frequency synchronization and per-subcarrier rotation synchronization.

Abstract: A method includes the steps of receiving (402), by a first receiver (102), a first received signal comprising a first signal (110) and a second signal (120), and receiving (402), by a second receiver (104), a second received signal comprising the first signal (110) and the second signal (120). A branch weight associated with the first receiver (102) and at least one other branch weight associated with the second receiver (104) are determined (406). The branch weight associated with the first receiver (102), the at least one other branch weight associated with the second receiver (102), the first received signal, and the second received signal are combined, forming a combined signal. Channel state information is determined for the combined signal, and the channel state information of the combined signal is restored (412).

Abstract: An apparatus (30) for and method of synchronizing OFDM signals utilizes a single baud to provide synchronization in time, frequency, and per-subcarrier rotation (201). Timing and fractional subcarrier frequency synchronization may be obtained from either a known or unknown (e.g., data symbol) baud having known symmetry properties. Because all three synchronization tasks may be accomplished utilizing a single sync baud, the present invention spectrally efficient. A differential correlation metric is utilized to efficiently provide integer subcarrier frequency synchronization and per-subcarrier rotation synchronization.

Abstract: A method includes the steps of receiving (402), by a first receiver (102), a first received signal comprising a first signal (110) and a second signal (120), and receiving (402), by a second receiver (104), a second received signal comprising the first signal (110) and the second signal (120). A branch weight associated with the first receiver (102) and at least one other branch weight associated with the second receiver (104) are determined (406). The branch weight associated with the first receiver (102), the at least one other branch weight associated with the second receiver (102), the first received signal, and the second received signal are combined, forming a combined signal. Channel state information is determined for the combined signal, and the channel state information of the combined signal is restored (412).

Abstract: The present invention provides a method, system, subscriber unit, and base/headend unit for a bandwidth efficient multiple user digital communication system that facilitates multiple user reverse link communication using overlapped transmit signal spectra of at least two overlap bandwidth subscriber units. Overlap bandwidth subscriber units receive a forward link signal, each deriving a frequency reference from the forward link signal and a symbol timing reference from the forward link signal, and transmitting a reverse link signal to the base/headend unit that receives a composite reverse link signal of the reverse link signals. Each reverse link signal includes at least one modulated data carrier with distinct carrier frequencies. Each transmitted reverse link signal has a symbol timing responsive to the symbol timing reference, and the frequency spectra of the reverse link signals overlap using overlapped transmit signal spectra of at least two overlap bandwidth subscriber units.