Realtek Semiconductor Inc.

Tsung-Chun Cheng

Der-Zheng Liu

Yen-Chih Chen

Wei-Hsuan Chang

Shau-Yu Cheng

Cheng-Deom Hasio

A communication device includes a radio transceiver and a processor. The radio transceiver is configured to transmit or receive wireless signals and includes a collision detection device. The collision detection device is configured to detect energy in a wireless communication channel during a first time interval before a packet is transmitted by the radio transceiver and accordingly generate a detection result. The first time interval covers a period of time for the radio transceiver to switch from a receiving state to a transmitting state. The processor is configured to adjust at least one transmission parameter according to the detection result.

Methods for adjusting transmission parameters and communication device utilizing the same

A sphere decoding method applied to a MIMO channel is provided. Multiple constellation points of an ndetection layer corresponding to a MIMO channel matrix are enumerated based on an enumeration rule, and at least one nsub-set of the ndetection layer is defined. K constellation points are obtained from each of the at least one nsub-set as preferred points, and Kpreferred points are selected from all the K preferred points of the at least one nsub-set. Kpreferred points are transferred to a second detection layer from a first detection layer. Kpreferred points are transferred to a Tdetection layer from a (T&#x2212;1)detection layer. An optimal solution is determined according to Kpreferred points of the ndetection layer. K and at least one of Kto Kare determined by the The characteristic of the MIMO channel matrix.

Sphere decoding method applied to multi-input multi-output (MIMO) channel

A sphere decoding method applied to a MIMO channel is provided. T signals transmitted via the MIMO channel are received. A first triangular matrix corresponding to a channel matrix is generated and mapped from the complex domain into the real domain to obtain a second triangular matrix. A first zero-forcing soft-output solution corresponding to a first estimation layer is found, and multiple preferred points P(1) are obtained. Multiple n-th zero-forcing soft-output solutions corresponding to an n-th estimation layer are obtained according to multiple preferred points P(n&#x2212;1), and multiple preferred points P(n) are obtained according to PEDs of multiple n-th constellation points. Multiple 2T-th zero-forcing soft-output solutions are obtained according to the preferred points P(2T&#x2212;1) and multiple preferred points P(2T) are obtained correspondingly. The preferred point P(2T) corresponding to the least PED is mapped from the real domain into the complex domain to generate an optimal solution of the T signals.

A sphere decoding method applied to a MIMO channel is provided. Multiple constellation points of an ndetection layer corresponding to the MIMO channel matrix are enumerated based on an enumeration rule, and at least one nsub-set of the nth detection layer is defined. The constellation point with the least PED is obtained as a preferred point. Another constellation, not in the nsub-set, of the nth detection layer is selected to substitute for the preferred point as one of the nsub-set. If other preferred points are needed to be obtained, the nsub-set is updated repeatedly according to the least PED. An optimal solution is determined according to Kpreferred points of the ndetection layer.

A sphere decoding method applied to a MIMO channel is provided. Multiple constellation points of an ndetection layer corresponding to a MIMO channel matrix are enumerated based on an enumeration rule, and at least one nsub-set of the ndetection layer is defined. The candidate range of the constellation points of the at least one nsub-set is determined according to a predetermined number K of the preferred points of the at least one nsub-set. K constellation points are obtained from the at least one nsub-set as the preferred points according to partial Euclidean distances of the constellation points. The at least one nsub-set includes at least K constellation points. Kpreferred points are selected from all K preferred points of the at least one nsub-set. An optimal solution is determined according to the K, preferred points.

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Taipei County, Taiwan

Tsung-Chun Cheng