Abstract: A method and system are disclosed for decoding block codes using a single decoder and trellis diagram. The signal can include at least one block code, and the block code can be modulated using at least one of a plurality of modulation modes. The block code contained in the signal can be selectively decoded based on the modulation mode for the block code using a trellis diagram corresponding to the modulation mode for the block code, for example, a low and high-rate CCK modulation mode or a differential quadrature phase shift keying (DQPSK) Baker sequence modulation mode and a differential binary phase shift keying (DBPSK) Barker sequence modulation mode. The trellis diagram can have multiple embedded subtrellis diagrams in the trellis diagram. In this manner, multiple types of block codes and be decoded using a single decoder and trellis diagram.

Abstract: An apparatus and method for calculating bit metrics in data receivers. The apparatus of the invention includes a storage unit and a calculator. The storage unit is configured to store a number of modulation-dependent coefficients; it selects as output one of the coefficients in accordance with a modulation mode being used. The calculator receives the selected coefficient from the storage unit and takes a received signal and a channel response in the frequency domain. According to the selected coefficient, the received signal and the channel response, the calculator generates at least N number of bit metrics for an N-bit codeword in the received signal.

Abstract: A method is directed to recovering a digital data content in a communication system, wherein the digital data content has been converted into an analog signal based on a primary clock, at a transmitter for transmitting to a receiver. The method comprises receiving the analog signal by the receiver. The analog signal is converted into a digital signal, based on a clock of the receiver. The digital signal is interpolated at the desired interpolation point, if digital signal in time has been shifted by an amount equal to or larger than a predetermined time length. The interpolated digital signal is recovered back to the digital data content, with the assist of an estimated channel impulse response. The channel impulse response is retrained every time when the interpolation point is significantly changed.

Abstract: A method and system are disclosed that provide a more efficient decoder for decoding block codes such as a complementary code keying (CCK) code. A receiver receives a signal containing at least one block codeword. A decoder decodes the block codeword contained in the received signal by finding a path in a trellis diagram with a calculated path metric that accounts for intersymbol interference (ISI). The path metric can be based on a branch metric that is calculated according to a decision feedback sequence estimation algorithm.

Abstract: A method for transmission rate adaptation used in a wireless network. A current transmission rate is selected from a set of predetermined transmission rates. Each of the predetermined transmission rates, R, is associated with a PER (packet error rate) range, which includes a predetermined threshold pair of a high PER threshold, denoted as QH(R), and a low PER threshold, denoted as QL(R). First, calculate a first estimated PER, denoted as P1(rn), wherein rn denotes the current transmission rate. Then, check whether the P1(rn) is larger than the QH(rn), if yes, reduce the transmission rate. Then, calculate a second estimated PER, denoted as P2(rn), and check whether the P2(rn) is smaller than the QL(rn), if yes, increase the transmission rate. And, check whether the P2(rn) being larger than the QH(rn), if yes, reduce the transmission rate.

Abstract: An apparatus and method for calculating bit metrics in data receivers. The apparatus of the invention includes a storage unit and a calculator. The storage unit is configured to store a number of modulation-dependent coefficients; it selects as output one of the coefficients in accordance with a modulation mode being used. The calculator receives the selected coefficient from the storage unit and takes a received signal and a channel response in the frequency domain. According to the selected coefficient, the received signal and the channel response, the calculator generates at least N number of bit metrics for an N-bit codeword in the received signal.

Abstract: A method is directed to recovering a digital data content in a communication system, wherein the digital data content has been converted into an analog signal based on a primary clock, at a transmitter for transmitting to a receiver. The method comprises receiving the analog signal by the receiver. The analog signal is converted into a digital signal, based on a clock of the receiver. The digital signal is interpolated at the desired interpolation point, if digital signal in time has been shifted by an amount equal to or larger than a predetermined time length. The interpolated digital signal is recovered back to the digital data content, with the assist of an estimated channel impulse response. The channel impulse response is retrained every time when the interpolation point is significantly changed.