A method and apparatus for determining placement of a plurality of antennas of a distributed antenna system for handling MIMO signals includes, at a first location, simulating the communication of a first MIMO signal by a first remote unit over an air interface in an environment and, at a second location, simulating the communication of a second MIMO signal by a second remote unit over an air interface in the environment. The first and second locations are arranged within the environment to provide overlapping signal coverage of both the first MIMO signal and the second MIMO signal at a third location in the environment. Analysis is made of at least an imbalance of received power between the first and second MIMO signals within the environment at a third location in order to determine whether a desired capacity for MIMO communications with the system has been achieved at the third location.

Distributed antenna system for mimo communications

In generating a data unit for transmission via a communication channel, a preamble of the data unit is generated, including i) generating a set of training fields, and ii) mapping each training field in the set of training fields to a plurality of space-time streams. When the set of training fields consist of four training fields, each training field in the set of training fields is mapped to four space-time streams according to a first space-time stream mapping matrix. When the set of training fields consists of six training fields, each training field in the set of training fields is mapped to six space-time streams according to a second space-time stream mapping matrix, wherein the first space-time stream mapping matrix is not a submatrix of the second space-time stream mapping matrix. A data portion of the data unit is generated so that a receiver device can receive the data portion via a corresponding number of space-time streams using channel information derived from the set of training fields.

PHY frame formats in a system with more than four space-time streams

Provided is a technology of accurately grasping a transmission status when shadowing occurs. A wireless communication device includes transmitting means wirelessly transmitting test signals a predetermined number of times at an interval shorter than a transmission interval of data signals and measuring means measuring reception status of a plurality of acknowledgement signals transmitted back in response to the respective test signals transmitted by the transmitting means.

Wireless communication device and wireless communication method

A communication system comprises evolved base nodes (eNBs) communicating via an over-the-air (OTA) link with low mobility user equipment (UE). A network can utilize the eNBs for cooperative beam shaping for interference nulling based upon a number of factors UE (e.g., coordinated multi-point (COMP) optimization for feedback, quality of service (QoS), fairness, etc.). The UE advantageously transmits adaptive rate and payload channel state feedback, trading accuracy versus delay based upon mobility of the UE. Channel coherence across a transmission interval (frequency and/or time invariance) provides an opportunity with sufficiently low mobility for transmitting a larger accuracy feedback report over one or more feedback reports for decoding at the eNB. Reduced quantization error can be realized via multi-level coding, one codebook multiple description coding (MDC), and use of N-best code representations from one codebook with MDC.

Method and apparatus for channel feedback in a wireless communication system

Methods and apparatuses for information feedback and precoding have been provided. A method for processing communication data at a user equipment in a wireless communication system may comprise: deriving a spatial correlation matrix R of multiple transmit antennas of a base station based on an obtained downlink channel transmission matrix H ; transforming a precoding codebook F according to the spatial correlation matrix R ; selecting a precoding matrix F s based on the transformed precoding codebook; and feeding back information about the spatial correlation matrix R and information about the selected precoding matrix F s to the base station. A method for data precoding at a base station in a wireless communication system may comprise: obtaining, from a user equipment, information about a spatial correlation matrix R of multiple transmit antennas of the base station and information about a precoding matrix F s selected by the user equipment; determining a desired precoding matrix F R,s based on the obtained information and a precoding codebook; and precoding downlink data to be transmitted to the user equipment with the desired precoding matrix F R,s

Method and apparatus for information feedback and pre-coding

An antenna apparatus and a method for controlling an antenna array are provided. The method includes the following steps. A plurality of selectable antenna configurations is provided for a directional service. One of the antenna configurations is selected for an antenna element of the antenna array according to a service criterion. The antenna apparatus includes an antenna array, a controller, and a switching unit. The antenna array includes a plurality of antenna elements. The controller is adapted to generate a control signal based on selecting one of a plurality of antenna configurations according to a service criterion for an antenna element to provide a directional service. The switching unit is adapted to configure each of the antenna elements according to the control signal.

Antenna apparatus and method for controlling antenna array

A spatial mapping matrix searching apparatus may include a plurality of antennae configured to receive a plurality of transmission signals, a post-coding module configured to generate a post-coding information according to the received plurality of transmission signals and generate a received signal from the received plurality of transmission signals, and a pre-coding module configured to generate a pre-coding information according to the post-coding information.

Method and apparatus for spatial mapping matrix searching

A method for transmitting data represented by a plurality of coded bits includes: allocating the coded bits to a plurality of groups; rearranging, for a retransmission of the coded bits, ones of the coded bits allocated to a first one of the plurality of groups to a second one of the plurality of groups, and ones of the coded bits allocated to the second one of the plurality of groups to the first one or a third one of the plurality of groups; and changing, for the retransmission, a sequence of coded bits allocated to each of the plurality of groups after the rearranging.

System and method for bit allocation and interleaving

This paper presents an extrinsic data compression method for double-binary turbo codes. Frame and extrinsic data memory occupy more area in turbo decoder implementations with the frame size increasing. Besides, non-binary turbo codes have much more extrinsic memory usage than single-binary turbo codes. This proposed compression method utilizes an operation in radix-4 single-binary turbo decoder and also can simplify the integration of single and double-binary turbo decoders in hardware implementations. It can reduce one-third of extrinsic memory size, about 15% of total memory usage. Simulation results show that this method only causes 0.2dB performance loss when bit error rate is equal to 10−5 with slight hardware increment.

Extrinsic data compression method for double-binary turbo codes

HARQ (hybrid automatic-repeat-request) enhances system throughput by improving SNR and gaining time diversity through retransmissions. To utilizing the coding gain, this paper classifies the priority of FEC coded bits and rearranges the bits for each retransmission at MSB (most significant bit) positions or LSB (less significant bit) positions of modulation symbols according to their priorities. In Addition to time diversity, the proposed HARQ gains frequency and spatial diversities. With themaximum retransmissions of two, numerical simulations showthat the proposed scheme outperforms the conventional ChaseCombining (CC) HARQ and Incremental Redundancy (IR) HARQ for WiMAX systems in terms of BLER (block error rate)and throughput with maximum SNR (signal-to-noise ratio) gainsof 3.5dB and 3dB, respectively.

Chien-Yu Kao

Papers

Antenna apparatus and method for controlling antenna array

Method and apparatus for spatial mapping matrix searching

System and method for bit allocation and interleaving

Extrinsic data compression method for double-binary turbo codes

Enhanced HARQ Using Prioritized Bit Selection and Rearrangement for WiMAX Systems