Motorola Corporation

Motorola Solutions, Inc.

Young-Seo Park

Darrell James Stogner

Charles R Ruelke

Yadunandana N Rao

Charles H Carter

Ariel L Galan

Lavanya Doblatyvenkata

A receiver for a wireless communication device provides a dual path receiver receiving first and second protocol-agnostic, uncorrelated receive signals simultaneously. The dual path receiver generating first and second offset IF signals from the simultaneously received first and second protocol-agnostic, uncorrelated receive signals. The receiver utilizes at least one converter for converting the first and second offset IF signals into at least one serial synchronous interface (SSI) signal representing the spectrum at IF. At least one processor receives the at least one SSI signal and applies parallel processing paths to demodulate the at least one SSI signal into separate baseband signals. The processor provides interference detection of, and level control for, the first and second offset IF signals.

Apparatus and method for a dual watch receiver

A method for controlling peak-to-average power ratio prior to amplification by a power amplifier is provided. The peak sample of a signal is predicted, window length is adjusted based on the peak width around the peak sample or subcarriers used to transmit the signal, and the window is subsequently used to clip the samples. A peak suppression window may be applied prior to predicting the peak sample when a set number of samples exceed a predetermined threshold. Window clipping may be deactivated if interference and throughput of the power amplifier is detrimentally affected. A pulse shaping filter may be optimized based on the window clipping to control transmitted signal characteristics. Various thresholds used in the prediction may be initially based on system design and power amplifier linearity and then dynamically adjusted based on an estimation of active subcarriers or of interferers present in the communication system.

Method for controlling peak-to-average power ratio of single carrier FDMA system

A system and a method to enlarge the minimum signal of a linear modulation signal () including multi-carrier modulation, such as Scalable advanced Modulation or Orthogonal Frequency Division Multiplexing, are disclosed. A minimum enlarger () exploits a simple amplitude limiter () so as not to interfere with an existing peak suppression scheme. The amplitude limiter () enlarges local minimum amplitude values to a predetermined minimum amplitude threshold if the local minimum amplitude values are less than the predetermined minimum amplitude threshold. While the amplitude limiter () adjusts the local minimum amplitude values in the linear modulation signal (), the phase of the linear modulation signal () is maintained. The conditioned linear modulation signal () increases the efficiency of a linear power amplifier (). The spectral change of the linear modulation signal due to the disclosed scheme is negligible because the adjusted signal power is negligible.

System and method for enlarging amplitude minima in a linear modulation signal

An improved multicarrier modulation system and method is introduced which has the advantages of both isotropic orthogonal transfer algorithm orthogonal frequency division multiplexing (IOTA OFDM) and scalable advanced modulation (SAM). The invention reduces adjacent channel interference (ACI) in the multicarrier modulation system used in multicast systems by generating () a spectrally efficient modified pulse for multicarrier modulation and then adapting () the pulse at the edge of the subchannel for reducing the ACI product by the total multicarrier signal (). This BTRRC OFDM () is an Offset OFDM with BTRRC pulse () while the prior art RRC OFDM () is an Offset OFDM with RRC pulse (). BTRRC OFDM has characteristics similar to RRC OFDM and has better power efficiency in simulcast or Nakagami fading environments where there is a timing error. Thus, BTRRC OFDM is desirable to substitute SAM in a simulcast environment.

Method for generating better than root raised cosine orthogonal frequency division multiplexing (BTRRC OFDM)

An improved multicarrier modulation system and method, which has the advantages of both isotropic orthogonal transfer algorithm orthogonal frequency division multiplexing (IOTA OFDM) and scalable advanced modulation (SAM), is introduced. The invention is root raised cosine (RRC) OFDM using the most spectrally efficient RRC filter without sacrificing the compact subchannel spacing of OFDM. The invention further provides an adjacent channel interference (ACI) suppression scheme and a modified RRC for better suppressing ACI of RRC OFDM. The ACI suppression scheme can also be applied to SAM with the modified RRC and to IOTA OFDM with a modified IOTA. The invention greatly improves a major problem of conventional OFDM namely ACI due to the use of a wide subchannel filter. Thus, the invention allows OFDM to meet even the strictest ACI requirements, which was not possible by using a conventional raised cosine windowing method.

System and method for generating a modified IOTA pulse for reducing adjacent channel interference (ACI) in an isotropic orthogonal transfer algorithm (IOTA) orthogonal frequency division multiplexing (OFDM) system

System and method for generating a spectral efficient root raised cosine (RRC) pulse for increasing spectral efficiency

System and method for generating a root raised cosine orthogonal frequency division multiplexing (RRC OFDM) modulation

A multi-carrier modulation communications system and method () for providing channel estimation that uses a transmitter for inserting pilot symbols in a digital multi-carrier modulated radio frequency (RF) signal and a receiver for receiving the pilot symbols in multi-carrier modulation RF signal. In order to provide channel estimation the receiver detects () channel power gains from a plurality of designated pilot symbols and calculates () both a speed parameter (S) and a multi-path parameter (M) for the channel receiving the pilot symbols. A channel model is then defined () based upon the speed parameter and multi-path parameter value and a predefined set of pilot coefficients is chosen () that substantially matches the channel model. The resulting set of pilot coefficients is then utilized () for optimizing pilot symbol interpolation.

Channel condition estimation for pilot coefficient selection

A method and device for adaptive quantization of soft bits includes numerically sorting soft bits of an external data block having a log likelihood ratio distribution of the soft bits, each of the soft bits having a value, the sorted soft bits having extreme values, determining two point values in the log likelihood ratio distribution of the data block respectively located at a clipping distance away from each extreme value of the sorted soft bits, defining an adapted quantization range with a half-length equal to half of a difference between the two point values or with a half-length equal to a larger of two absolute values of the two point values, and placing each of the soft bits within a respective sub-range of the adapted quantization range. An adapted quantization range is determined whenever the log likelihood ratio distribution of the data block changes.

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Sunrise, FL, United States of America

Young-Seo Park