Motorola Corporation

Motorola Mobility LLC

Nikhil Shashank Nadgauda

Kevin Lynn Baum

Brian Keith Classon

Frederick W Vook

James Robert Kelton

Roger L Peterson

Roger Laurin Peterson

An apparatus () for and method of synchronizing OFDM signals utilizes a single baud to provide synchronization in time, frequency, and per-subcarrier rotation (). 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.

Method and apparatus for synchronizing an OFDM signal

A method includes the steps of receiving (), by a first receiver (), a first received signal comprising a first signal () and a second signal (), and receiving (), by a second receiver (), a second received signal comprising the first signal () and the second signal (). A branch weight associated with the first receiver () and at least one other branch weight associated with the second receiver () are determined (). The branch weight associated with the first receiver (), the at least one other branch weight associated with the second receiver (), 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 ().

Method and apparatus for restoring a soft decision component of a signal

A method (300), system (400), base station (500), head-end unit (600), and subscriber unit (700) provide for efficient resource management in a communication system or group of communication systems supporting a plurality of communication units, where different communication units may have varying resource size requirements. The method includes the steps of: determining a resource size requirement of a communication unit of the plurality of communication units, determining a hierarchical level within the hierarchy that the communication unit is to be assigned to based on the resource size requirement of the communication unit, and assigning the communication unit to an available resource slot in the hierarchical level in accordance with a predetermined hierarchical management scheme that maximizes a total number of remaining available slots in the hierarchy.

Hierarchical resource management method, system, base station, head-end

A method (300), system (400), base station (500), head-end unit (600), and subscriber unit (700) provide for efficient resource hopping in a communication system or group of communication systems supporting a plurality of communication units, where different communication units may have varying resource size requirements. The method includes the steps of: assigning a communication unit of the plurality of communication units to a resource slot within a level of a plurality of levels of a hierarchical representation of a resource region, assigning an available resource hopping pattern and associated initial resource location within the resource slot to the communication unit, and hopping, by the communication unit in accordance with a predetermined hierarchical resource hopping scheme.

Hierarchical resource hopping method, system, base station, head-end

A synchronous coherent orthogonal frequency division multiplexing, SC-OFDM, system, method, software and device include a plurality of SC-OFDM transmitters and a plurality of SC-OFDM receivers. Each of the plurality of SC-OFDM transmitters is synchronized to a reference where the reference is derived from a common source, for transmitting SC-OFDM signals. The plurality of SC-OFDM receivers is arranged to receive the SC-OFDM signals from at least one of the plurality of SC-OFDM transmitters. The SC-OFDM signals each have a cyclic extension, and the SC-OFDM signals from each SC-OFDM transmitter include at least one pilot code in accordance with a predetermined pilot code scheme.

Synchronous coherent orthogonal frequency division multiplexing system,

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.

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Chicago, IL, United States of America

Nikhil Shashank Nadgauda