Abstract: A high performance real-time turbo code system is proposed. The proposed system exploits cooperative coding architecture and a proper decoding scheduling to achieve low error rate within a constrained latency. Permutation schemes and hardware embodiments utilizing the cooperative coding are also shown. Various memory saving techniques are provided to reduce memory usage in both encoder and decoder. The proposed system is compatible with 3rd generation mobile standards and cost of designing new parts exclusively for the proposed system can be minimized. This invention can provide substantial coding and system capacity gains for real-time applications in a wireless environment.

Abstract: A model-based channel estimator for correlated fading channels adapted to a multiple-input multiple-output (MIMO) system, estimates a coefficient vector of a channel matrix for a given angle of departure (AoD) according to a plurality of received signals, a plurality of transmit pilots, a plurality of known model orders, and a plurality of predetermined bases for exploiting time, frequency, spatial channel correlation among a transmit antenna array, and spatial channel correlation among a receive antenna array, then estimates a mean AoD based on the estimated channel matrix. The channel estimator estimates iteratively the coefficient vector and the mean AoD until a stop criterion is met. Then, it reconstructs a channel estimate by using the plurality of predetermined bases, the coefficient vector, and the mean AoD.

Abstract: A model-based channel estimator for correlated fading channels adapted to a multiple-input multiple-output (MIMO) system, estimates a coefficient vector of a channel matrix for a given angle of departure (AoD) according to a plurality of received signals, a plurality of transmit pilots, a plurality of known model orders, and a plurality of predetermined bases for exploiting time, frequency, spatial channel correlation among a transmit antenna array, and spatial channel correlation among a receive antenna array, then estimates a mean AoD based on the estimated channel matrix. The channel estimator estimates iteratively the coefficient vector and the mean AoD until a stop criterion is met. Then, it reconstructs a channel estimate by using the plurality of predetermined bases, the coefficient vector, and the mean AoD.

Abstract: A method for estimating frequency offset is provided. First, a baseband signal with a preamble featuring quasi-periodic property is received. Next, the quasi-periodic property of the preamble of the received baseband signal is reconstructed by interpolation. Next, a frequency offset angle is estimated by using the reconstructed baseband signal. The accuracy of estimating frequency offset is increased because of better reconstructed quasi-periodic property of the preamble.

Abstract: A high performance real-time turbo code system is proposed. The proposed system exploits cooperative coding architecture and a proper decoding scheduling to achieve low error rate within a constrained latency. Permutation schemes and hardware embodiments utilizing the cooperative coding are also shown. Various memory saving techniques are provided to reduce memory usage in both encoder and decoder. The proposed system is compatible with 3rd generation mobile standards and cost of designing new parts exclusively for the proposed system can be minimized. This invention can provide substantial coding and system capacity gains for real-time applications in a wireless environment.

Abstract: This invention provides a sequence generating method, in which the method has steps of generating R sets of orthogonal sequence with each set of the orthogonal sequence including N elements, generating a low-autocorrelation sequence having N elements, and multiplying the N elements of the low-autocorrelation sequence by the N elements of each of R sets of the orthogonal sequence point-to-point. Therefore, a sequence generated by the method of the present invention has low-autocorrelation and low-crosscorrelation in transmission characteristics of a communication system.

Abstract: A method for estimating frequency offset is provided. First, a baseband signal with a preamble featuring quasi-periodic property is received. Next, the quasi-periodic property of the preamble of the received baseband signal is reconstructed by interpolation. Next, a frequency offset angle is estimated by using the reconstructed baseband signal. The accuracy of estimating frequency offset is increased because of better reconstructed quasi-periodic property of the preamble.

Abstract: A high performance real-time turbo code system is proposed. The proposed system exploits cooperative coding architecture and a proper decoding scheduling to achieve low error rate within a constrained latency. Permutation schemes and hardware embodiments utilizing the cooperative coding are also shown. Various memory saving techniques are provided to reduce memory usage in both encoder and decoder. The proposed system is compatible with 3rd generation mobile standards and cost of designing new parts exclusively for the proposed system can be minimized. This invention can provide substantial coding and system capacity gains for real-time applications in a wireless environment.