Motorola Corporation

Roger L Peterson

Eugene Visotsky

Thomas V D'Amico

Stephen Leigh Kuffner

Kevin Lynn Baum

James Robert Kelton

Michael Honig

Nikhil Shashank Nadgauda

Vinayak Tripathi

Peijuan Liu

Rodger E Ziemer

A DTV signal detector detects DTV signals received by a receiver on a selected DTV channel in a Digital Television System. The DTV detector includes a first DTV signal detector that detects a first characteristic of the received DTV signals, and a second DTV signal detector that detects at least a second characteristic of the received DTV signals. A controller responds to the first DTV signal detector and the second DTV signal detector to control a selection of the DTV channel being selected by the receiver. The receiver can be synthesized to select from more than one DTV channel.

Detector for digital television signal

A technique for dynamic spectrum sharing includes identifying () a plurality of radio nodes (), measuring () a local signal value (SV) at each radio node (), and determining () a transmit decision. Each radio node can measure a local signal value (SV) of a protected transmission and the radio nodes are within a uniform SV region of the protected transmission. The transmit decision is determined for at least one of the plurality of radio nodes based on the SV of each radio node in the plurality of radio nodes and at least one threshold value that is related to statistical characteristics of the protected transmission at an interference boundary () of the protected transmission and a desired probability of non-interference with the protected transmission at the interference boundary.

Method and apparatus for dynamic spectrum sharing

A method and apparatus for signal detection is provided herein. During operation logic circuitry will determine if a de-sensing signal exists within any received signal and, if a de-sensing signal exists, then it will be assumed that a radar pattern exists where the de-sensing signal exists within the signal. Any received signal pattern is then correlated to known radar transmission pattern in order to determine whether or not a radar transmission pattern was received. If a known transmission pattern was received then logic circuitry will prevent further transmission.

Method and apparatus for signal detection

A communication system is designed that reduces co-channel interference when heterogeneous users are sharing spectrum. The system design enables a plurality of pairs of users to communicate their channel utilization time periods by using the durations and start or stop times of certain transmissions to signal the start times and durations of later transmissions. Other system users using possibly different communications protocols and different modulation technologies can measure the durations of received transmissions and to infer channel usage based on these durations.

Method and apparatus for reducing interference within a communication system

A communication system employs a HARQ-type retransmission scheme. Bits ( ) received on a first transmission are stored and combined with the bits received on later transmissions thereby increasing the likelihood of a correct decoding on later transmissions. Similarly the bits received on the second or later transmissions are stored for combining with subsequent received bits. Specific information needed at the receiver is identified and requested from the transmitter. More particularly, information that is retransmitted in a second or later transmission in the HARQ scheme is determined from a reliability of individual constituent bits in the mother codeword or from an overall reliability of the received codeword. Based on these reliability metrics, the most unreliable set of the constituent bits are requested or, in the alternative, a specific number of constituent bits is requested.

Reliability-based type-II hybrid ARQ scheme

A communication system facilitates multi-rate data transmission by using a set (N) (210) of spreading codes from which a subset (n) (214) of the spreading codes is dynamically selected based on a first set of bits from source digital information to be transmitted. The subset (214) of spreading codes are simultaneously transmitted and used for coding a second set of bits from the source digital information. A receiver has correlators (306-309) to correlate each of the set of spreading codes with a received spread spectrum signal (302) to produce correlated signals. A code subset estimation circuit (312) is coupled to each correlator (306-309) and determines the magnitude of each of the correlated signals. The code subset estimation circuit (312) selects a subset of spreading codes from the set of spreading codes based on the magnitude of all correlated signals and determines the polarity of the subset of codes to decode the encoded received data.

Method and apparatus for facilitating multi-rate data transmission by

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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Inverness, IL, United States of America

Roger L Peterson