Abstract: A multi-receiver wireless communication device includes a transmitter, a transmit oscillator communicatively coupled to the transmitter, a receive oscillator communicatively coupled to a first receiver and second receiver, and a switching assembly having a first state in which the receive oscillator is coupled to the first and second receivers and a second state in which the receive oscillator is de-coupled from the second receiver and the transmit oscillator is coupled to the second receiver. The first receiver and the second receiver of the wireless communication device are able to operate independent of one another when the switching assembly is in the second state.

Abstract: A multi-receiver wireless communication device includes a transmitter, a transmit oscillator communicatively coupled to the transmitter, a receive oscillator communicatively coupled to a first receiver and second receiver, and a switching assembly having a first state in which the receive oscillator is coupled to the first and second receivers and a second state in which the receive oscillator is de-coupled from the second receiver and the transmit oscillator is coupled to the second receiver. The first receiver and the second receiver of the wireless communication device are able to operate independent of one another when the switching assembly is in the second state.

Abstract: A method of communication using Orthogonal Frequency Division Multiplexing (“OFDM”) comprises generating bit streams (bn?(0,1),n=0,1, . . . ,K?1) and the corresponding sets of frequency domain carrier amplitudes (XO(k) to XN(k)), where k is the OFDM symbol number, modulated as OFDM symbols to be transmitted from a transmitter. Prefixes are inserted as guard intervals in the sample streams and the OFDM symbols are transmitted from the transmitter to a receiver. The receiver uses information from the prefixes to estimate the Channel Impulse Response (H(F)D) of the transmission channels and uses the estimated Channel Impulse Response (?(F)D) to demodulate the bit streams in the signals received. The prefixes (?k.co to ?k.cD?1) are deterministic and are known to the receiver as well as to the transmitter. Preferably, the prefixes (?k.co to ?k.cD?1) comprise a vector (PD) that is common to said symbols multiplied by at least one weighting factor (?k).

Abstract: A method for conversion of signals between analog and digital characterised by; applying a non-linear transfer function to an input signal, such that the relation between the quantisation levels of the converter and the input signal vary as a non-linear function of the magnitude of the input signal. The non-linear transfer function is related to the probability density function of the input signal so that larger quantisation bins of the converter correspond to less probable values of the input signal.

Abstract: A method for analog to digital conversion (ADC) characterised by; applying a non-linear transfer function to an input signal, such that the relation between the quantisation levels of the converter and the input signal vary as a non-linear function of the magnitude of the input signal. The non-linear transfer function is related to an at least approximate measurement of probability density function ‘p(x)’ of said input signal so that larger quantisation bins of the converter correspond to less probable values of the input signal. The relation is iteratively updated by updating quantisation levels.

Abstract: A method of communication using Orthogonal Frequency Division Multiplexing (“OFDM”) comprises generating bit streams (bn?(0,1),n=0,1, . . . ,K?1) and the corresponding sets of frequency domain carrier amplitudes (XO(k) to XN(k)), where k is the OFDM symbol number, modulated as OFDM symbols to be transmitted from a transmitter. Prefixes are inserted as guard intervals in the sample streams and the OFDM symbols are transmitted from the transmitter to a receiver. The receiver uses information from the prefixes to estimate the Channel Impulse Response (H(F)D) of the transmission channels and uses the estimated Channel Impulse Response (?(F)D) to demodulate the bit streams in the signals received. The prefixes (?k.co to ?k.cD?1) are deterministic and are known to the receiver as well as to the transmitter. Preferably, the prefixes (?k.co to ?k.cD?1) comprise a vector (PD) that is common to said symbols multiplied by at least one weighting factor (?k).

Abstract: A Viterbi decoder includes a number of classical Add-Compare-Select units and a number of further Add-Compare-Select unit having a lower complexity butterfly unit (300) having only two adder means, such that the further Add-Compare-Select unit has a butterfly unit (300) comprising: first adder means (310) for receiving a first path metric and a branch metric and for producing at its output the addition thereof; and second adder means (320) for receiving a second path metric and said branch metric and for producing at its output the addition thereof. First comparator means (330) are coupled to receive the output of the second adder means and coupled to receive the first path metric for comparing therebetween. Second comparator means (340) are coupled to receive the output of the first adder means and coupled to receive the second path metric for comparing therebetween.

Abstract: A Viterbi decoder including an Add-Select-Compare unit with a new butterfly unit (300) having only two adders (310, 320), compared with a conventional butterfly unit's four adders, for processing a trellis transition having branch metric of zero. The new butterfly unit (300) is thus of reduced complexity (saving 8% of the total Viterbi decoder complexity in a typical example).