Abstract: 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.

Abstract: 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.

Abstract: Method and module for judging status alterations of power supplies that are caused by changes of external power sources are provided. Through comparing first, second and third comparison voltages with a stabilized voltage of a voltage stabilization and energy storage element in a power factor correction unit, the status of the power supply can be judged, and an external power supply abnormal signal, a power supply abnormal signal or a power failure alert signal can be generated according to the status to allow a motherboard to perform loading regulation. The power failure alert signal is used to timely stop operation of the power supply, hence can resolve the problems of the conventional techniques such as delay notification, inaccurate judgment or complex composition of judgment circuit.

Abstract: A sphere decoding method applied to a MIMO channel is provided. Multiple constellation points of an nth detection layer corresponding to a MIMO channel matrix are enumerated based on an enumeration rule, and at least one nth sub-set of the nth detection layer is defined. K constellation points are obtained from each of the at least one nth sub-set as preferred points, and Kn preferred points are selected from all the K preferred points of the at least one nth sub-set. K1 preferred points are transferred to a second detection layer from a first detection layer. K(T?1) preferred points are transferred to a Tth detection layer from a (T?1)th detection layer. An optimal solution is determined according to Kn preferred points of the nth detection layer. K and at least one of K1 to KT are determined by the The characteristic of the MIMO channel matrix.

Abstract: 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?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?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.

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

Abstract: A sphere decoding method applied to a MIMO channel is provided. Multiple constellation points of an nth detection layer corresponding to the MIMO channel matrix are enumerated based on an enumeration rule, and at least one nth sub-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 nth sub-set, of the nth detection layer is selected to substitute for the preferred point as one of the nth sub-set. If other preferred points are needed to be obtained, the nth sub-set is updated repeatedly according to the least PED. An optimal solution is determined according to Kn preferred points of the nth detection layer.

Abstract: 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?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?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.

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

Abstract: A sphere decoding method applied to a MIMO channel is provided. Multiple constellation points of an nth detection layer corresponding to the MIMO channel matrix are enumerated based on an enumeration rule, and at least one nth sub-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 nth sub-set, of the nth detection layer is selected to substitute for the preferred point as one of the nth sub-set. If other preferred points are needed to be obtained, the nth sub-set is updated repeatedly according to the least PED. An optimal solution is determined according to Kn preferred points of the nth detection layer.

Abstract: A sphere decoding method applied to a MIMO channel is provided. Multiple constellation points of an nth detection layer corresponding to a MIMO channel matrix are enumerated based on an enumeration rule, and at least one nth sub-set of the nth detection layer is defined. K constellation points are obtained from each of the at least one nth sub-set as preferred points, and Kn preferred points are selected from all the K preferred points of the at least one nth sub-set. K1 preferred points are transferred to a second detection layer from a first detection layer. K(T?1) preferred points are transferred to a Tth detection layer from a (T?1)th detection layer. An optimal solution is determined according to Kn preferred points of the nth detection layer. K and at least one of K1 to KT are determined by the The characteristic of the MIMO channel matrix.

Abstract: The invention provides a wireless communication apparatus with performance simulation function. The wireless communication apparatus includes a channel emulator and at least one noise generator; therefore a real transmission environment can be simulated inside the wireless communication apparatus to thereby accelerate the testing process. Moreover, as this invention sets a random noise generator in front of the FFT, an approximate AWGN effect will be generated when the wireless communication apparatus is under test.

Abstract: Doppler principle has been widely applied to calculate the velocity of the object in motion. In medical ultrasonic imaging, it can be used to detect blood flow or myocardial motion. However, due to the inherent limitation of the Doppler effect, the measured velocity is only the projection of the actual velocity onto the ultrasound beam direction instead of the actual velocity. In previously proposed methods for measuring or correcting the Doppler angles, some need manual correction, others use complicated algorithms. They are either inconvenient to use or difficult to implement in current systems. In the method of Doppler motion detection with automatic angle correction according to the instant invention, it focuses on the relation between the Doppler angle and signal bandwidth to compute the Doppler angle by efficient correlation processing. Specifically, it uses variance of the Doppler signal to approximate square of the Doppler bandwidth.