Abstract: Disclosed is a wireless communication signal peak-to-average power ratio reduction, method. The method comprises calculating a peak envelope from an envelope of an input signal using a clipping threshold; smoothing the peak envelope using a window function; mapping the smoothed peak envelope to an attenuation function using the clipping threshold; and applying the attenuation function to the input signal.

Abstract: A transmission signal pre-processing method and apparatus for out-of-band emission cancellation are disclosed. For each of N subchannels in a band weighting each of N subchannel symbols by a calculated value in the range from 0 to 1 is performed. Precoding said N weighted symbols, organised as an N×1 matrix, by multiplication by a unitary matrix is then performed.

Abstract: A wireless data communications method and transmitter are disclosed. A transmitter (402N, 800) includes a module (802) configured to group adjacent sub-bands from among a set of transmission radio frequency channels assigned to a terminal into a plurality of aggregated sub-bands. A single carrier modulator (804) is configured to modulate data symbols in at least some of said aggregated sub-bands. A combining module (808) is configured to combine said single carrier modulated signals into a multi-carrier signal. A receiver (502N, 900) is also provided in conjunction with the transmitter (800) to constitute a transceiver.

Abstract: In one embodiment, a demapper uses two hybrid-QPSK constellations to demap pairs of equalized data symbols recovered from 16-QAM, DCM OFDM symbols, wherein the equalized data symbols in a pair correspond to the same four-bit group. A first hybrid-QPSK constellation is generated by combining the real components of both 16-QAM mapping constellations onto one coordinate plane. The demapper generates a first set of two decision variables by combining the real components of each equalized data symbol in a pair to correspond to the first hybrid-QPSK coordinate plane. A log-likelihood ratio is then calculated for both decision variables in the set to determine likelihood estimates for the first and second bits of the four-bit group. This process is repeated for the imaginary components of each corresponding pair of equalized data symbols to generate likelihood estimates for the third and fourth bits of the four-bit group.

Abstract: Disclosed is a hybrid antenna array (100) comprising a plurality of digital branches (145), each digital branch including an analogue beamforming sub-array (e.g. 110-1), each sub-array having a plurality of antenna elements (120), a phase shifter (130) adapted to apply a phase shift to the signal from each antenna element, and a combiner (e.g. 135-1) adapted to combine the phase-shifted signals. Each digital branch also includes a signal chain (e.g. 140-1) adapted to convert the output of the sub-array to baseband.

Abstract: In one embodiment, a demapper uses two hybrid-QPSK constellations to demap pairs of equalized data symbols recovered from 16-QAM, DCM OFDM symbols, wherein the equalized data symbols in a pair correspond to the same four-bit group. A first hybrid-QPSK constellation is generated by combining the real components of both 16-QAM mapping constellations onto one coordinate plane. The demapper generates a first set of two decision variables by combining the real components of each equalized data symbol in a pair to correspond to the first hybrid-QPSK coordinate plane. A log-likelihood ratio is then calculated for both decision variables in the set to determine likelihood estimates for the first and second bits of the four-bit group. This process is repeated for the imaginary components of each corresponding pair of equalized data symbols to generate likelihood estimates for the third and fourth bits of the four-bit group.

Abstract: Disclosed is a method of processing a series of data bits for transmission on a transmit link, the method comprising mapping the series of data bits to a series of data symbols; demultiplexing the series of data symbols to a plurality of substreams of symbols; modulating each substream of symbols to a corresponding series of OFDM symbols; and space precoding the plurality of series of OFDM symbols to form one or more series of space precoded OFDM symbols, wherein the demultiplexing is dependent on channel state information for the transmit link.

Abstract: Disclosed is a modulation method, comprising dividing a series of data bits into a plurality of contiguous blocks; composing each block into a corresponding parallel packet; mapping one or more bits from each parallel packet into a corresponding data symbol; and modulating the data symbols onto respective subcarriers of an OFDM symbol.

Abstract: A method of block spreading data, the method comprising the steps of: (a) providing a first input data sequence; (b) forming a periodic extension of the input data sequence to form an extended input data sequence; (c) multiplying the extended input data sequence by a complex number spreading sequence to produce a spread signal sequence; and (d) outputting the spread signal sequence.

Abstract: In one embodiment, a transmitter converts digital input data into combined-OFDM signals and a receiver recovers data from the transmitted combined-OFDM signals. For transmission, digital data is mapped into data symbols using a commonly known modulation technique, such as QAM or DQPSK. The data symbols are subsequently divided into two or more groups according to a specified grouping pattern. Each group of data symbols is then converted into a separate OFDM subsymbol using IFFT processing. The OFDM subsymbols are then combined according to a specified combining pattern to create a combined-OFDM symbol. Combined-OFDM symbols are then prepared for transmission by affixing cyclic prefixes, converting the symbols to analog format, and performing spectral shaping of the analog signal. Upsampling may be employed to increase the signal bandwidth. In alternative embodiments, OFDM subsymbols may be combined using interleaving to create an interleaved-OFDM symbol.

Abstract: In one embodiment, a demapper uses two hybrid-QPSK constellations to demap pairs of equalized data symbols recovered from 16-QAM, DCM OFDM symbols, wherein the equalized data symbols in a pair correspond to the same four-bit group. A first hybrid-QPSK constellation is generated by combining the real components of both 16-QAM mapping constellations onto one coordinate plane. The demapper generates a first set of two decision variables by combining the real components of each equalized data symbol in a pair to correspond to the first hybrid-QPSK coordinate plane. A log-likelihood ratio is then calculated for both decision variables in the set to determine likelihood estimates for the first and second bits of the four-bit group. This process is repeated for the imaginary components of each corresponding pair of equalized data symbols to generate likelihood estimates for the third and fourth bits of the four-bit group.

Abstract: A method and system for interactive channel equalization uses channel status information included in data packets. The system includes a first station adapted to transmit a first data packet including a channel status information segment over a radio communication channel as a first signal. A second station in the system includes a static pre-equalizer and an adaptive equalizer. The second station is adapted to receive the first signal and adaptively equalize the first signal using the adaptive equalizer and the channel status information to create a post hoc status estimate of the channel. The second station is further adapted to transmit a second data packet over the channel as a second signal, where the second signal is pre-equalized by the pre-equalizer using the post hoc status estimate of the channel. The method and system thus enable parameters of the channel equalization to be adjusted in real-time in response to varying channel conditions.

Abstract: A method and system for interactive channel equalization uses channel status information included in data packets. The system includes a first station adapted to transmit a first data packet including a channel status information segment over a radio communication channel as a first signal. A second station in the system includes a static pre-equalizer and an adaptive equalizer. The second station is adapted to receive the first signal and adaptively equalize the first signal using the adaptive equalizer and the channel status information to create a post hoc status estimate of the channel. The second station is further adapted to transmit a second data packet over the channel as a second signal, where the second signal is pre-equalized by the pre-equalizer using the post hoc status estimate of the channel. The method and system thus enable parameters of the channel equalization to be adjusted in real-time in response to varying channel conditions.

Abstract: A filter bank (10) and receiver including the filter bank (10) that is designed for processing a baseband signal of a received continuous phase modulated signal S(t) with an integer modulation index. The filter bank (10) has outputs for providing a plurality of decision variable values (d1,d2,d3,d4) each representing a likelihood value of a symbol, from a group of predefined symbols that are likely to be present in the continuous phase modulated signal S(t). The filter bank 10 has filter units (12,14,16,18) each having an impulse response determined by a complex main pulse containing a majority of signal energy of one of the predefined symbols that is likely to be in the continuous phase modulated signal S(t).

Abstract: A communications unit (2) and method (50) for providing a transmission packet (30), the transmission packet (30) comprising a data independent field (32) and a payload field (33). The unit (2) and method (50) performs processing digital data (54) to provide a modulated digital payload. The method then performs a step (55) of obtaining pre-defined modulated transmission protocol bits stored in a memory. Then a combining step (56) provides for combining the modulated digital payload and the predefined modulated transmission protocol bits to provide the transmission packet (30), wherein the modulated digital payload is in the payload field (33) and the modulated transmission protocol bits are in the data independent field (32).

Abstract: A device (100) and method (700) for creating a spread spectrum signal by providing a complementary code spreading signal (740) having an auto-correlation function of zero, for any non-zero offset, at integer multiples of a selected time interval. The method includes modulating (750) a data stream with the complementary code spreading signal to provide the spread spectrum signal.

Abstract: A method, system and electronic device (100) for providing a partially encrypted data packet in a spread spectrum signal. The device has a spread spectrum signal encoder (140) having a data input, an output and a plurality of modulators (202,204,206) with inputs respectively coupled to outputs of a direct sequence generator (110), a scrambling sequence generator (120) and a carrier generator (125). There is also an output unit (150) coupled to an output of the spread spectrum signal encoder (140). In use when a data packet comprising a payload field of bits and non-payload field of bits is received by the spread spectrum signal encoder (140), the modulators (202,204,206) modulate the data packet to provide the partially encrypted data packet with the payload being a spread spectrum signal encrypted by a scrambling sequence from the scrambling sequence generator (120) and the non-payload field comprises a spread spectrum signal free of encryption by said scrambling sequence.

Abstract: A filter bank (10) and receiver including the filter bank (10) that is designed for processing a baseband signal of a received continuous phase modulated signal S(t) with an integer modulation index. The filter bank (10) has outputs for providing a plurality of decision variable values (d1,d2,d3,d4) each representing a likelihood value of a symbol, from a group of predefined symbols that are likely to be present in the continuous phase modulated signal S(t). The filter bank 10 has filter units (12,14,16,18) each having an impulse response determined by a complex main pulse containing a majority of signal energy of one of the predefined symbols that is likely to be in the continuous phase modulated signal S(t).

Abstract: An electronic device (100) for providing a multi-carrier spread spectrum signal. The device (100) has a spread spectrum signal encoder (140) and decoder (160). The encoder has sequence spreading modules (143) and modulators (145) each having a unique carrier frequency relative to all other carrier frequencies of the other modulators (145). The encoder (140) converts a received serial data stream of bits into a plurality of parallel data bit streams of different bit lengths, and expand a received one of the parallel data bit streams into a coded bit sequences. Each of the coded bit sequences have a unique time period relative to all other said coded bit sequence from every other sequence spreading modules (143) of the encoders (140). The decoder (160) decodes received multi-carrier spread spectrum signals into data bit streams.

Abstract: A system and electronic device (100) for providing a spread spectrum signal. The device (100) has a modulator (140), digital signal providing circuitry (130) coupled to the modulator (140), a modulation pseudo noise sequence generator (110) having a sequence output coupled to the modulator (140) and an output unit (150) coupled to the modulator (140). In use, the digital signal providing circuitry (130) provides data bits each of which is modulated, by the modulator (140), with a pseudo noise sequence supplied from modulation pseudo noise sequence generator (110) to thereby provide the spread spectrum signal that is transmitted by the output unit (150). There is also a demodulator (170) and input unit (160) for demodulating received spread spectrum signals.