Abstract: A wireless communication method implemented in a communication system may include receiving a data sequence to be permuted, and obtaining information associated with the data sequence to be permuted, the information containing at least a length of the data sequence and a sampling spacing for permuting the data sequence. The method may also include identifying a first portion of the data sequence having a first number of adjacent data items, and a second portion of the data sequence having a second number of adjacent data items. The method may also include accessing the first number of data items from the first portion at the sampling spacing, and placing the accessed first number of data items into a predetermined number of sub-blocks included within a permuted data sequence to be generated based on the received data sequence.

Abstract: A wireless communication method implemented in a communication system includes receiving a first data sequence, and processing the first data sequence to obtain information containing at least one of a first number and a sampling spacing associated with the first data sequence. The method also includes permuting the first data sequence to generate a permuted second data sequence. Permuting the first data sequence includes determining a first parameter based on at least one of the first number and the sampling spacing, determining a second parameter based on at least one of the first parameter, the first number, and the sampling spacing, and determining a mapping relationship between a j-th data item of the permuted second data sequence and an i-th data item of the first data sequence. The method further includes outputting the permuted second data sequence.

Abstract: A wireless communication method may include receiving a first data stream comprising a data sequence and computing a permutation sequence based on a content of the received first data stream. The permutation sequence is a non-predetermined sequence. The method may further include performing a permutation on the first data stream based on the permutation sequence to generate a permuted first data stream being configured for wireless transmission.

Abstract: Methods and systems for providing generalized link adaptation in an orthogonal frequency-division multiple access wireless communications network can include determining a number of desired resource blocks (RBs) for each user of a plurality of users; calculating a maximal channel gain Gm for each RB of a plurality of RBs; reordering the plurality of RBs based on the Gm; assigning one of the plurality of RBs to the plurality of users one-by-one according to the reordering of the plurality of RBs; determining a priority list for assigning remaining unassigned RBs; assigning the remaining unassigned RBs to the plurality of users based on the priority list; and mapping a symbol or a packet to each assigned RB.

Abstract: A method for a mobile station to provide to a base station feedback of channel state information (CSI) regarding a plurality of communication channels between the mobile station and the base station. The method includes: estimating the CSI by calculating a plurality of channel responses each for one of the communication channels; compressing the estimated CSI; and sending the compressed CSI as the feedback to the base station.

Abstract: 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.

Abstract: A method and apparatus for transmitting data in a MIMO communication system, the method including encoding at least one data symbol by implementing a first precoding scheme, the first preceding scheme including a precoder derived from a first channel state information (CSI). The method further includes selecting at least one antenna that maximizes the first CSI, the at least one antenna being selected by implementing a first selection scheme, and transmitting the at least one data symbol via the at least one antenna.

Abstract: In a multiple input multiple output (MIMO) wireless communication system, there is provided a method for error correction. The method includes receiving an original signal in an initial MIMO format, detecting an error in the original signal, and notifying a transmitter of the error detected in the original signal. The method also includes receiving a new retransmitted signal in a first retransmitted MIMO format, different from the initial MIMO format, the new retransmitted signal including at least a fraction of encoded bits of the original signal. The method also includes correcting the original signal by applying the new retransmitted signal to the original signal.

Abstract: A method for pilot design for data to be transmitted by an orthogonal frequency-division multiplexing (OFDM) based communication system, the data being represented by a plurality of OFDM symbols. The method includes allocating pilot symbols for a data stream to be included in ones of the OFDM symbols; and performing a frequency shift on at least one of the OFDM symbols, to reduce frequency distance disparities among the pilot symbols.

Abstract: A method for removing ICI for a received symbol is provided. Firstly, a transmitted symbol is received via a wireless channel within a symbol time so as to obtain the received symbol. The transmitted symbol includes P identical original partial data, wherein P is a positive integer larger than 1. The received symbol includes P received partial data corresponding to the original partial data, respectively. Next, on a time domain at least two of the P received partial data are copied so as to obtain at least two copied partial data. Each copied partial data includes P copies of its corresponding received partial data. After that, an estimated ICI of the time domain is determined according to the product of a predetermined constant array and the difference between the copied partial data. Afterwards, the estimated ICI is subtracted from the received symbol so as to obtain an output symbol.

Abstract: A DC offset estimation system is disclosed. A DC offset estimation system includes a carrier frequency offset estimator receiving an input signal and estimating a carrier frequency offset value, a symbol timing recovery unit providing a symbol boundary of the input signal, and a DC offset estimator estimating a DC offset value to compensate the input signal based on the input signal, the carrier frequency offset value, and the symbol boundary.

Abstract: A module constructs a frame for communication in a communication system that supports a new standard and a legacy standard, the new standard being backward compatible with the legacy standard. The module comprises a first frame generator configured to generate a first portion of the frame, the first portion of the frame to support a first set of data to be transmitted in the legacy standard in each of a number of first bands, a second frame generator configured to generate a second portion of the frame, the second portion of the frame to support a second set of data to be transmitted in the new standard in a second band composed of the first bands, and a frame constructor configured to construct the frame based on the first portion of the frame from the first frame generator and the second portion of the frame from the second frame generator.

Abstract: In one aspect of the invention, a carrier frequency offset (CFO) estimation method to estimate a CFO value of a received signal is provided, and the method comprises: receiving a preamble signal which includes several non-perfect repeat segments; applying an interpolation procedure to interpolate the perfect repeat point of one segment compared with the next segment or the previous segment; acquiring a delay correlation value based on the two perfect repeat signal segments and estimating the CFO value based on the delay correlation value.

Abstract: A method and OFDM receiver for estimating timing offset. The method comprises the method of receiving OFDM data to calculate frequency offset between a transmitter carrier frequency and a receiver carrier frequency, the method of determining first timing offset based on the frequency offset, the method of compensating the OFDM data with the first timing offset, the method of estimating a residual common phase based on the compensated OFDM data, the method of determining second timing offset based on the residual common phase, and the method of compensating the OFDM data with the second timing offset, if the frame symbol index exceeds the predetermined data length.

Abstract: A maximum likelihood detection (MLD) method is disclosed. Received data is processed to obtain preliminary parameters. An initial radius r is determined. r2 is multiplied by a corresponding scaling factor according to a partial Euclidean distance (PED) constraint function to determine the upper limit values of PED for each layer. It is examined whether a sub-lattice exceeds a search scope according to the upper limit values of PED for each layer to search a better solution by utilizing the preliminary parameters.

Abstract: Fractional carrier frequency offset estimators and related methods are disclosed. The invention may be particularly applied in WiMAX systems. The disclosed method of estimating fractional carrier frequency offset between a transmitter and a receiver includes calculating a first delay correlation based on a first and a second preamble repetitions included in a received signal, processing the phase of the first delay correlation to compensate for a phase rotation of the first delay correlation, and estimating the fractional carrier frequency offset by multiplying a processed phase value, generated after the step of processing the phase of the first delay correlation, by a predetermined value.

Abstract: A guard section length detection method detects whether a preamble signal is received. A short preamble boundary is then detected, then detecting a frame boundary and detecting a guard section length. In the step of detecting the guard section length a second matched filter capable of processing 128 point data sets is detected. Four different 128 point data sets have a distance of 8 points, 16 points, 32 points, and 64 points respectively from the frame boundary to the second matched filter. Four signal correlation values are calculated for determining the guard section length.