Abstract:
PAPR reduction using Active Constellation Extension for both two dimensional (2D) non-square constellations (or non-uniform constellations like APSK) and for square constellations (usual QAM constellations) called one dimensional (1D). The receiver applies after the FFT for each symbols either a scalar limiter for 1D constellations or a constant modulus (circular) limiter for 2D constellations.
Abstract:
A signal scrambling method is provided for peak-to-average power ratio (PAPR) reduction of STBC MIMO-OFDM signals in a MIMO-OFDM system having Y transmit antenna. In general terms the OFDM sequence of symbols in said signal for each transmit antenna is divided into M sub-blocks of equal size and subclockwise rotation and inversions are performed across all transmit antennas to generate [2Y] M permuted sequence sets from the original OFDM sequence. Based on a predetermined criteria, there is then selected from the resulting sets of OFDM sequences the one with the best PAPR properties for transmission. The predetermined criteria preferably comprises identifying maximums for all [2Y] M sequence sets, by calculating the largest PAPR value of Y sequences in each set and selecting a set with the minimum maximum for transmission.
Abstract:
A method for data transmission by a device in a communication system includes modulating a first data stream using a codebook to produce a second data stream, wherein the codebook is in correspondence with a multi-dimensional modulation map that includes a number of distinct projections per complex dimension that is smaller than a number of modulation points of the multi-dimensional modulation map, and transmitting the second data stream over allocated resources in the communication system.
Abstract:
A transmitting apparatus is disclosed. The transmitting apparatus includes an encoder to perform channel encoding with respect to bits and generate a codeword, an interleaver to interleave the codeword, and a modulator to map the interleaved codeword onto a non-uniform constellation according to a modulation scheme, and the constellation may include constellation points defined based on various tables according to the modulation scheme.
Abstract:
Even when communication is performed independently in each CC (Component Carrier), the occurrence of an error in communication is prevented. Provided is a wireless communication system in which a wireless transmission apparatus and a wireless reception apparatus communicate with each other using a plurality of system frequency bands, wherein the wireless transmission apparatus performs transmission power control on transmission data in each of the system frequency bands, and furthermore, a maximum transmission power which can be transmitted in each of the system frequency bands can be controlled so as to be different from each other. Priorities are set on each of the system frequency bands, and transmission powers of the system frequency bands are determined in descending order of the priorities.
Abstract:
Transmission power of a signal may be lowered in response to detecting a broadcast radio transmission. A communication device may communicate via a powerline communication (PLC) medium by transmitting, via the PLC medium, a signal having at least a first carrier frequency. The communication device may detect a broadcast radio transmission. The communication device may lower a transmission power setting associated with the first carrier frequency from a first power level to a second power level that is lower than the first power level in response to detecting the broadcast radio transmission. The communication device may transmit, via the PLC medium, the signal having at least the first carrier frequency at the second power level during a time period associated with the broadcast radio transmission.
Abstract:
A transmitting apparatus is disclosed. The transmitting apparatus includes an encoder to perform channel encoding with respect to bits and generate a codeword, an interleaver to interleave the codeword, and a modulator to map the interleaved codeword onto a non-uniform constellation according to a modulation scheme, and the constellation may include constellation points defined based on various tables according to the modulation scheme.