Abstract: A multi-user downlink orthogonal frequency-division multiple access (OFDMA) configuration method includes: assigning contiguous resource units (RUs) included in a channel to a plurality of stations, respectively; and assigning, by an access point (AP), one modulation and coding scheme (MCS) to each of the plurality of stations. Data rates of modulation and coding schemes that are assigned to first stations and associated with contiguous first RUs assigned to the first stations are monotonic, where the first stations are included in the plurality of stations.

Abstract: A multi-user downlink orthogonal frequency-division multiple access (OFDMA) configuration method includes: assigning contiguous resource units (RUs) included in a channel to a plurality of stations, respectively; and assigning, by an access point (AP), one modulation and coding scheme (MCS) to each of the plurality of stations. Data rates of modulation and coding schemes that are assigned to first stations and associated with contiguous first RUs assigned to the first stations are monotonic, where the first stations are included in the plurality of stations.

Abstract: A signal processing apparatus includes a signal generating block arranged to generate a target estimated signal of a specific signal component in an input signal. The signal generating block includes a reference signal generating circuit, a signal processing circuit, and a signal adjusting circuit. The reference signal generating circuit is arranged to generate a reference estimated signal for the specific signal component in the input signal. The signal processing circuit is coupled to the reference signal generating circuit, and arranged to process the reference estimated signal and accordingly generate a signal processing result. The signal adjusting circuit is coupled to the signal processing circuit and the reference signal generating circuit, and arranged to output the target estimated signal by adjusting the reference estimated signal according to the signal processing result.

Abstract: A method for determining a Doppler shift of a first signal is provided. First, a plurality of Doppler frequency hypotheses is combined to obtain a joint Doppler signal. The first signal is the correlated according to the joint Doppler signal and a plurality of code signals with phases corresponding to a series of code phase hypotheses to obtain a series of correlation results which are then examined to determine whether the Doppler shift does lie in the Doppler hypotheses. A fine Doppler search is then performed to determine the Doppler shift when the Doppler shift lies in the Doppler hypotheses.

Abstract: A configurable calculating circuit includes a multiplexer, a mixer and an accumulator. The multiplexer is for receiving input signals including at least a first and a second input signals, and selectively outputting at least one of the input signals. The mixer is for mixing a selected input signal outputted from the multiplexer with a local oscillation signal to generate a mixed signal. The accumulator is for accumulating the mixed signal to generate an accumulated signal. When the configurable calculating circuit is operated under a first mode, the multiplexer selects the first input signal, and the accumulator performs a first accumulating operation upon the mixed signal; and when the configurable calculating circuit is operated under a second mode, the multiplexer selects the second input signal, and the accumulator performs a second accumulating operation, different from the first accumulating operation, upon the mixed signal.

Abstract: A signal processing apparatus includes a signal generating block arranged to generate a target estimated signal of a specific signal component in an input signal. The signal generating block includes a reference signal generating circuit, a signal processing circuit, and a signal adjusting circuit. The reference signal generating circuit is arranged to generate a reference estimated signal for the specific signal component in the input signal. The signal processing circuit is coupled to the reference signal generating circuit, and arranged to process the reference estimated signal and accordingly generate a signal processing result. The signal adjusting circuit is coupled to the signal processing circuit and the reference signal generating circuit, and arranged to output the target estimated signal by adjusting the reference estimated signal according to the signal processing result.

Abstract: A configurable calculating circuit includes a multiplexer, a mixer and an accumulator. The multiplexer is for receiving input signals including at least a first and a second input signals, and selectively outputting at least one of the input signals. The mixer is for mixing a selected input signal outputted from the multiplexer with a local oscillation signal to generate a mixed signal. The accumulator is for accumulating the mixed signal to generate an accumulated signal. When the configurable calculating circuit is operated under a first mode, the multiplexer selects the first input signal, and the accumulator performs a first accumulating operation upon the mixed signal; and when the configurable calculating circuit is operated under a second mode, the multiplexer selects the second input signal, and the accumulator performs a second accumulating operation, different from the first accumulating operation, upon the mixed signal.

Abstract: A gain control method is provided. In one embodiment, an amplifier amplifies a first signal according to a gain to obtain a second signal, and a converter converts the second signal to a digital signal. First, the gain is sequentially set to a plurality of gain values. A plurality of entropy values of the digital signal corresponding to the gain values is then calculated. A picked entropy value of the entropy values is then determined. The gain value corresponding to the picked entropy value is then determined as a picked gain value. Finally, the gain is set to the picked gain value for amplifying the first signal.

Abstract: A gain control method is provided. In one embodiment, an amplifier amplifies a first signal according to a gain to obtain a second signal, and a converter converts the second signal to a digital signal. First, the gain is sequentially set to a plurality of gain values. A plurality of entropy values of the digital signal corresponding to the gain values is then calculated. A picked entropy value of the entropy values is then determined. The gain value corresponding to the picked entropy value is then determined as a picked gain value. Finally, the gain is set to the picked gain value for amplifying the first signal.

Abstract: A jamming detector and jamming detecting method are disclosed. In accordance with the present invention, distribution of a received signal is compared with a reference distribution of a specific signal model. Deviation of the signal distribution from the reference distribution can be obtained according to the comparison results. The existence of jamming is determined according to the deviation. If the signal distribution significantly deviates from the reference distribution, it means that jamming exists. An anti-jamming circuit or algorithm can be activated only when jamming is detected, thereby power consumption is reduced.

Abstract: A method for determining a Doppler shift of a first signal is provided. First, a plurality of Doppler frequency hypotheses is combined to obtain a joint Doppler signal. The first signal is the correlated according to the joint Doppler signal and a plurality of code signals with phases corresponding to a series of code phase hypotheses to obtain a series of correlation results which are then examined to determine whether the Doppler shift does lie in the Doppler hypotheses. A fine Doppler search is then performed to determine the Doppler shift when the Doppler shift lies in the Doppler hypotheses.

Abstract: A method of direct RF digitization for multiple RF signal bands such GNSS or wireless communication signal bands and a receiver using the method. By using the method, an optimal sampling frequency to be used in direct RF digitization for signals of multiple RF signal bands can be easily obtained. According to the present invention, one or more of the RF signal bands are selected to be shifted to target band(s). By doing so, the optimal sampling frequency can be easily calculated. Then the obtained sampling frequency is used in executing the direct RF digitization.

Abstract: A method and apparatus for collecting subframes of navigation data of satellites are disclosed. In the method of the present invention, the subframe is divided into several sub-units, each sub-units includes one or more words. When a receiver receives a subframe with a subframe ID, the respective required sub-units of the subframe are checked. A dummy sub-unit is not necessary to be considered. Valid ones of the required sub-units are collected. If not all the required sub-units of the subframe have been collected, the absent sub-units are to be collected when the next subframe with the same subframe ID is received. Some protection schemes can be applied to raise the reliability of such sub-unit collection. Especially when the signal is weak or unstable, the present invention may significantly improve the TTFF (Time To First Fix) performance of the receiver.

Abstract: A method and apparatus for collecting subframes of navigation data of satellites are disclosed. In the method of the present invention, the subframe is divided into several sub-units, each sub-units includes one or more words. When a receiver receives a subframe with a subframe ID, the respective required sub-units of the subframe are checked. A dummy sub-unit is not necessary to be considered. Valid ones of the required sub-units are collected. If not all the required sub-units of the subframe have been collected, the absent sub-units are to be collected when the next subframe with the same subframe ID is received. Some protection schemes can be applied to raise the reliability of such sub-unit collection. Especially when the signal is weak or unstable, the present invention may significantly improve the TTFF (Time To First Fix) performance of the receiver.

Abstract: A GNSS satellite signal handling method is disclosed. For a specific Doppler bin, when a peak is found, it is checked if the specific Doppler bin is polluted with interference by detection. If the detection result indicates that the specific Doppler bin is polluted with interference, a threshold, which is used to determine whether the actual signal peak is found or not, is then raised to a higher level, so as to increase the searching reliability. To detect interference, it is determined whether the specific Doppler bin is polluted by comparing a statistical value of correlation results of a plurality of code chip hypotheses with a reference or by checking if there are plural peaks existing in the power spectrum.

Abstract: A jamming detector and jamming detecting method are disclosed. In accordance with the present invention, distribution of a received signal is compared with a reference distribution of a specific signal model. Deviation of the signal distribution from the reference distribution can be obtained according to the comparison results. The existence of jamming is determined according to the deviation. If the signal distribution significantly deviates from the reference distribution, it means that jamming exists. An anti-jamming circuit or algorithm can be activated only when jamming is detected, thereby power consumption is reduced.

Abstract: A method and apparatus for collecting subframes of navigation data of satellites are disclosed. In the method of the present invention, the subframe is divided into several sub-units, each sub-units includes one or more words. When a receiver receives a subframe with a subframe ID, the respective required sub-units of the subframe are checked. A dummy sub-unit is not necessary to be considered. Valid ones of the required sub-units are collected. If not all the required sub-units of the subframe have been collected, the absent sub-units are to be collected when the next subframe with the same subframe ID is received. Some protection schemes can be applied to raise the reliability of such sub-unit collection. Especially when the signal is weak or unstable, the present invention may significantly improve the TTFF (Time To First Fix) performance of the receiver.

Abstract: A method of direct RF digitization for multiple RF signal bands such GNSS or wireless communication signal bands and a receiver using the method. By using the method, an optimal sampling frequency to be used in direct RF digitization for signals of multiple RF signal bands can be easily obtained. According to the present invention, one or more of the RF signal bands are selected to be shifted to target band(s). By doing so, the optimal sampling frequency can be easily calculated. Then the obtained sampling frequency is used in executing the direct RF digitization.