Abstract: A method for angle estimation verification, adapted for verifying an estimated angle calculated by an electronic apparatus having an angle estimator and at least three antennas, is provided. The estimated angle is extracted from the angle estimator. An autocorrelation matrix is generated according to a signal vector formed by a plurality of measurements of a received signal received by each of the antennas so as to obtain a plurality of eigenvalues. Among phase difference data generated by a plurality of antenna groups formed by all different combinations of two of the antennas, a plurality of possible estimated angles corresponding to the phase difference data not caused by a coterminal angle effect are calculated. According to the eigenvalues and the possible estimated angles, whether the received signal corresponds to a single target or multiple targets is determined so as to verify the reliability of the estimated angle.

Abstract: The present invention provides a method for identifying a specific number of communicating points having relatively smallest accumulated path values from a plurality of transmitting points for a receiving point in a communication system. The method includes steps of: (a) defining a first coordination of each of the plurality of transmitting points and the receiving point on a complex plane; (b) transferring the first coordination of the receiving point to a second coordination thereof, in which the second coordination of the receiving point is near an origin of the complex plane; and (c) identifying the specific number of transmitting points having relatively smallest accumulated path values based on the second coordination of the receiving point.

Abstract: A motion parameter estimating method, an angle estimating method and a determination method are provided. The methods are adapted for an electronic device. In the angle estimating method, a first frequency modulation continuous wave signal is first transmitted, and at least one antenna receives a second frequency modulation continuous wave signal resulted by a target reflecting the first frequency modulation continuous wave signal. Multiple motion parameters associated with the target are then obtained according to the first frequency modulation continuous wave signal and the second frequency modulation continuous wave signal. Multiple measured values corresponding to the at least one antenna are obtained according to the motion parameters and configuration parameters of the at least one antenna, respectively. Afterwards, the measured values are substituted into a formula to obtain an estimated angle between a preset direction of the electronic device and the target.

Abstract: The present invention provides a method for identifying a specific number of communicating points having relatively smallest accumulated path values from a plurality of transmitting points for a receiving point in a communication system. The method includes steps of: (a) defining a first coordination of each of the plurality of transmitting points and the receiving point on a complex plane; (b) transferring the first coordination of the receiving point to a second coordination thereof, in which the second coordination of the receiving point is near an origin of the complex plane; and (c) identifying the specific number of transmitting points having relatively smallest accumulated path values based on the second coordination of the receiving point.

Abstract: The present invention provides a method for identifying a specific number of communicating points having relatively smallest accumulated path values from a plurality of transmitting points for a receiving point in a communication system. The method includes steps of: (a) defining a first coordination of each of the plurality of transmitting points and the receiving point on a complex plane; (b) transferring the first coordination of the receiving point to a second coordination thereof, in which the second coordination of the receiving point is near an origin of the complex plane; and (c) identifying the specific number of transmitting points having relatively smallest accumulated path values based on the second coordination of the receiving point.

Abstract: A decoder for underdetermined MIMO systems with low decoding complexity is provided. The decoder consists of two stages: 1. Obtaining all valid candidate points efficiently by slab decoder. 2. Finding the optimal solution by conducting the intersectional operations with dynamic radius adaptation to the candidate set obtained from Stage 1. A reordering strategy is also disclosed. The reordering can be incorporated into the proposed decoding algorithm to provide a lower computational complexity and near-ML decoding performance for underdetermined MIMO systems.

Abstract: A decoder for underdetermined MIMO systems with low decoding complexity is provided. The decoder consists of two stages: 1. Obtaining all valid candidate points efficiently by slab decoder. 2. Finding the optimal solution by conducting the intersectional operations with dynamic radius adaptation to the candidate set obtained from Stage 1. A reordering strategy is also disclosed. The reordering can be incorporated into the proposed decoding algorithm to provide a lower computational complexity and near-ML decoding performance for underdetermined MIMO systems.

Abstract: An apparatus and a method for loading a predetermined number of bits into a plurality of sub-channels are provided. The apparatus comprises a sort module, a calculation module, and a decision module. The sort module is configured to sort the sub-channels into a plurality of sorted sub-channels according to the quality value of each of the sub-channels. The calculation module is configured to calculate the difference value for each of the sorted sub-channels, except for the first sorted sub-channel, according to the corresponding quality value. The decision module is configured to decide a number of bits for each of the sorted sub-channels according to the difference values, wherein a summation of the numbers is equal to the predetermined number. The apparatus and the method are able to load bits efficiently according to the difference values.

Abstract: An adaptive modulation and coding (AMC) method for data transmission by various modulation orders and coding rates is provided. A signal-to-noise ratio (SNR) of a transmission channel is estimated. Quality of service (QOS) parameters are provided, defining maximum allowable delay and packet error rate (PER). A retransmission limit is determined from the maximum allowable delay. An optimum packet length is determined based on the QOS parameters and the SNR. A modulation order and a coding rate most suitable for the estimated SNR and the defined PER are selected based on the optimum packet length and the retransmission limit.

Abstract: The present invention provides a method for identifying a specific number of communicating points having relatively smallest accumulated path values from a plurality of transmitting points for a receiving point in a communication system. The method includes steps of: (a) defining a first coordination of each of the plurality of transmitting points and the receiving point on a complex plane; (b) transferring the first coordination of the receiving point to a second coordination thereof, in which the second coordination of the receiving point is near an origin of the complex plane; and (c) identifying the specific number of transmitting points having relatively smallest accumulated path values based on the second coordination of the receiving point.

Abstract: A method for selecting a codeword in a multi-input multi-output (MIMO) communication system is disclosed. The method comprises steps providing a transmitter with codeword. A receiver receives the codeword candidates and calculates the corresponding bit error rate (BER) according to a decoding strategy. The receiver chooses a codeword candidate which has a minimum BER value and sends a selection signal to the transmitter. And, a transmitter determines a codeword for data transmission according to the selection signal.

Abstract: The invention provides a block-wise successive interference cancellation (SIC) detection algorithm for a general multi-input multi-output (MIMO) CDMA system over the frequency-selective channels, in which each user's data stream can be simultaneously applied with orthogonal space-time block encoding for transmit diversity or spatially multiplexing for high spectral efficiency according to the channel conditions. For such the considered dual-signaling system, the receiver could suffer from the large dimension data processing. A two-stage approach for block-wise SIC detection algorithm is thus proposed to further reduce the computational complexity.

Abstract: An apparatus and a method for loading a predetermined number of bits into a plurality of sub-channels are provided. The apparatus comprises a sort module, a calculation module, and a decision module. The sort module is configured to sort the sub-channels into a plurality of sorted sub-channels according to the quality value of each of the sub-channels. The calculation module is configured to calculate the difference value for each of the sorted sub-channels, except for the first sorted sub-channels, according to the corresponding quality value. The decision module is configured to decide a number of bits for each of the sorted sub-channels according to the difference values, wherein a summation of the numbers is equal to the predetermined number. The apparatus and the method are able to load bits efficiently according to the difference values.

Abstract: An apparatus for receiving OFDM signals via at least two antennae is disclosed. The apparatus includes a converter for converting a plurality of OFDM symbols received via each antenna to a plurality of sub carrier signals, wherein each sub carrier signal corresponds to one of a plurality of sub carriers; a combining unit for combining the sub carrier signals, which are obtained via each antenna and correspond to a specified sub carrier, based on a combining coefficient vector to form a combined signal; a recovery unit for recovering a desired signal based on the combined signal corresponding to the specified sub carrier; and a combining coefficient estimation unit for updating the combining coefficient vector corresponding to the specified sub carrier based on the desired signal corresponding to the specified sub carrier and the sub carrier signals, which correspond to the sub carrier and are obtained via each antennae.

Abstract: The present invention discloses a MIMO system and method, which is suitable for MC-CDMA communication system with multiple paths to obtain the spectrum efficiency and gain simultaneously. The transceiver performs steps of simultaneously transferring transmitting data to a plurality of parallel data streams, and space time block encoding each data, followed by spreading the encoded data streams with a pre-designed space-path spreading code, and transmitting data with the transmit antennas through multiple paths. Finally, at each receiver, despreading received data by the matched filters, and separating mutually interfering signals with a linear combiner and a BLAST detector to obtain the diversity gain.

Abstract: The present invention provides a communication system, signal pre-processing apparatus and signal receiving apparatus thereof. The signal pre-processing apparatus is used for pre-processing signals before they are transmitted by a plurality of antennas. The apparatus includes a serial-to-parallel converter, L compensation processors and L beam formation processors. First of all, the serial-to-parallel converter converts a digital signal into N divided signals. Each of the compensation processors pre-compensates the N divided signals and outputs a compensated signal. Each of the beam formation processors intensifies the compensated signal and outputs an intensified signal. Each of the antennas combines L intensified signals into a particular signal, and meanwhile, upconverts the particular signal into a RF (radio-frequency) signal for transmission.

Abstract: A method for selecting a codeword in a multi-input multi-output (MIMO) communication system is disclosed. The method comprises steps providing a transmitter with codeword. A receiver receives the codeword candidates and calculates the corresponding bit error rate (BER) according to a decoding strategy. The receiver chooses a codeword candidate which has a minimum BER value and sends a selection signal to the transmitter. And, a transmitter determines a codeword for data transmission according to the selection signal.

Abstract: A method and apparatus for estimation of frequency offset in wireless communications. Symbols to be transmitted are arranged in blocks of K symbols. The symbol blocks and their replicas are interleaved and then encoded into K sequences of coded symbols in space and time domains. The K coded symbol sequences are transmitted from K transmit antennas, while baseband signals carrying the coded symbols are received via J receive antennas and converted into J groups of intermediate signals. Thereafter, an interlaced operation and coherent combination is performed on each of the J intermediate signal groups. J sets of computed signals are thus generated and then combined in the space and time domains to develop a set of combined signals. Consequently, a frequency offset is estimated on the basis of this combined signal set.

Abstract: An adaptive modulation and coding (AMC) method for data transmission by various modulation orders and coding rates is provided. A signal-to-noise ratio (SNR) of a transmission channel is estimated. Quality of service (QOS) parameters are provided, defining maximum allowable delay and packet error rate (PER). A retransmission limit is determined from the maximum allowable delay. An optimum packet length is determined based on the QOS parameters and the SNR. A modulation order and a coding rate most suitable for the estimated SNR and the defined PER are selected based on the optimum packet length and the retransmission limit.

Abstract: An equalizer applied in a multiple input multiple output (MIMO) orthogonal frequency division multiplex (OFDM) system for alleviating interference among a plurality of received symbol blocks is disclosed. The equalizer includes: a matched filter for extracting a preliminary equalized signal vector from a received symbol block; a blocking device for generating a preliminary interference signal vector by attenuating a equalized signal vector from the received symbol block; a weighting device, electrically connected to the blocking device, for generating an interference signal vector by adjusting the preliminary interference signal vector; and a subtractor, electrically connected to the weighting device and the matched filter, for generating the equalized signal vector of the received symbol block according to the difference between the interference signal vector and the preliminary equalized signal vector.