摘要:
Some embodiments include devices, methods and/or systems of reduced peak-to-average-ratio communication. An apparatus may include a transmitter to transmit a transmission corresponding to an input signal, wherein the transmitter may include a peak-to-average-ratio-reduction transformer to generate a plurality of transformed data components by applying a predefined peak-to-average-ratio-reduction transform scheme to a plurality of fine constellation data components corresponding to the input signal, wherein a peak-to-average-ratio corresponding to the plurality of transformed data components is lower than a peak-to-average-ratio corresponding to the plurality of fine-constellation data components; and a transmission module to generate the transmission based at least on the plurality of transformed data components. Other embodiments are described and claimed.
摘要:
Some embodiments include devices, methods and/or systems of reduced peak-to-average-ratio communication. An apparatus may include a transmitter to transmit a transmission corresponding to an input signal, wherein the transmitter may include a peak-to-average-ratio-reduction transformer to generate a plurality of transformed data components by applying a predefined peak-to-average-ratio-reduction transform scheme to a plurality of fine constellation data components corresponding to the input signal, wherein a peak-to-average-ratio corresponding to the plurality of transformed data components is lower than a peak-to-average-ratio corresponding to the plurality of fine-constellation data components; and a transmission module to generate the transmission based at least on the plurality of transformed data components. Other embodiments are described and claimed.
摘要:
A first convolutional coder (building-block trellis coder) is used to establish a minimum squared Euclidian distance (MSED) between signal points within a coded constellation building block. A second convolutional encoder (tiling encoder) is designed to ensure that the building block's MSED is maintained between building blocks once they are tiled onto an integer lattice. When this approach is applied to the trellis code of the WiMAX standard, a 3 dB coding is realized. Recall that Wei's 16-state 4D code suffered from a 1.36 dB due to constellation expansion, resulting in a net 4.66 dB coding gain. Our building block approach recovers 1.33 dB of this loss with only a minor increase in coding complexity. We then use the building block approach to derive simpler and more powerful higher dimensional codes that provide further gains still over the Wei family of multidimensional codes.
摘要:
An adaptable orthogonal frequency-division multiplexing system (OFDM) that uses a multiple input multiple output (MIMO) to having OFDM signals transmitted either in accordance with time diversity to reducing signal fading or in accordance with spatial diversity to increase the data rate. Sub-carriers are classified for spatial diversity transmission or for time diversity transmission based on the result of a comparison between threshold values and at least one of three criteria. The criteria includes a calculation of a smallest eigen value of a frequency channel response matrix and a smallest element of a diagonal of the matrix and a ratio of the largest and smallest eigen values of the matrix.
摘要:
A downstream adaptive modulation system and method. The downstream adaptive modulation system comprises a wireless access termination system and one or more wireless modems. The wireless access termination system includes a plurality of queues and a parser. The parser parses data traffic onto the plurality of queues. Each queue is associated with a different coding and modulation scheme. Each of the one or more wireless modems receives data traffic from the plurality of queues based on the wireless modem's ability to demodulate and decode the signal from each of the plurality of queues. When a wireless modem experiences a change in signal strength, the present invention enables the wireless modem to adapt to data from other queues to compensate for the change in signal strength. Thus, if the signal strength improves over a period of time, the wireless modem may receive data at a higher order modulation and FEC code rate. If the signal strength weakens over a period of time, the wireless modem may receive data at a lower order modulation and FEC code rate.
摘要:
A multiservice is implemented by connecting one base station and one terminal via one wireless link.There is provided communication control means 2-1 that performs communication in compliance with an OFDMA scheme having traffic channels including first sub-channels for containing information showing enabled or disabled sub-channels and second sub-channels for storing data pertaining to services in correspondence with the first sub-channels, that allocates a plurality of first sub-channels to a plurality of services, respectively, and that connects one base station to one terminal via one wireless link, thereby establishing communication pertaining to the plurality of services.
摘要:
The present invention relates to allocating a radio resource in a wireless communication system utilizing orthogonal frequency division multiplexing (OFDM). Preferably, the present invention comprises receiving in a mobile station data associated with a radio resource allocation map from a base station, wherein the radio allocation map comprises control parameters for transmitting an uplink channel, wherein the uplink channel comprises at least one OFDM tile comprising a first set of subcarriers associated with representing at least part of an n-bit data payload, and a second set of subcarriers associated with representing at least part of a non-pilot m-bit data payload wherein each subcarrier carries a modulated data, and the first and the second set of subcarriers are exclusive to each other, and transmitting the uplink channel from the mobile station to the base station.
摘要:
Methods of using superposition coding in a communications systems, e.g., a multi-user communications system. Superposition coding in accordance with the invention occurs in the case of an uplink by transmissions of different wireless terminals transmitting using the same communications resource, e.g., simultaneously transmitting using the same frequencies. The signals combine in the communications channel resulting in one transmission being superimposed on the other transmission. The device, e.g., base station, receiving the superimposed signals uses superposition decoding techniques to recover both signals. To obtain the benefit of the superposition, assignments of channel segments to multiple wireless terminals is controlled by the base station and/or transmission power levels are controlled by on or more wireless terminals sharing the same uplink communications resource, e.g., time slot, to make sure that the received signals from the different devices will have different received power levels making superposition decoding possible.
摘要:
At the transmitter side, carrier waves are modulated according to an input signal for producing relevant signal points in a signal space diagram. The input signal is divided into, two, first and second, data streams. The signal points are divided into signal point groups to which data of the first data stream are assigned. Also, data of the second data stream are assigned to the signal points of each signal point group. At the receiver side, the first and/or second data streams can be reconstructed from a received signal. Furthermore, a communication system based on an OFDM system is utilized for data transmission of a plurality of subchannels, wherein the subchannels are differentiated by changing the length of a guard time slot or a carrier wave interval of a symbol transmission time slot, or changing the transmission electric power of the carrier.