Methods and apparatus for generating and communicating wireless signals having pilot signals with variable pilot signal parameters

A method for wirelessly communicating a signal, the method comprising the steps of:

• generating a wireless signal that includes a guard band, data represented within a plurality of data-bearing subcarriers, and a plurality of pilot signals represented within a plurality of pilot subcarriers, wherein the plurality of pilot signals have variable pilot signal parameters selected from a group of parameters that includes pilot power and pilot spacing with respect to adjacent pilots, and wherein generating the wireless signal comprises:
• combining a plurality of phase shifted input data signals with a plurality of synchronization/pilot sequences to produce a plurality of combined signals, wherein the plurality of synchronization/pilot sequences include the plurality of pilot signals,
• performing frequency domain-to-time domain transformations of the combined signals to produce a plurality of candidate signals,
• determining peak-to-average ratios for at least some of the plurality of candidate signals,
• identifying a selected signal from the plurality of candidate signals based on the peak-to-average ratios, and
• further processing the selected signal to generate the wireless signal;
• and
• transmitting the wireless signal over a wireless communication channel.

A method comprising the steps of:

• receiving a received signal from a wireless communication channel, wherein the received signal represents a channel-affected version of a wireless signal that was transmitted by a transmitter, and wherein the wireless signal includes a guard band, data represented within a plurality of data-bearing subcarriers, and a plurality of pilot signals represented within a plurality of pilot subcarriers, wherein the data-bearing subcarriers and the pilot subcarriers are within an in-band region, and wherein a power contained within one or more first pilot signals of the plurality of pilot signals is substantially different from a power contained within one or more second pilot signals of the plurality of pilot signals, and wherein the one or more first pilot signals and the one or more second pilot signals are simultaneously received;
• producing a corrected signal by applying corrections to the received signal based on estimated channel perturbations within the received signal, which estimated channel perturbations are determined based on the plurality of pilot signals;
• and
• producing an output data symbol from the corrected signal.

A method comprising the steps of:

• receiving a received signal from a wireless communication channel, wherein the received signal represents a channel-affected version of a wireless signal that was transmitted by a transmitter, and wherein the wireless signal includes a guard band, data represented within a plurality of data-bearing subcarriers, and a plurality of pilot signals represented within a plurality of pilot subcarriers, wherein the plurality of pilot signals have variable pilot signal parameters selected from a group of parameters that includes pilot power and pilot spacing with respect to adjacent pilots, wherein the wireless signal that was transmitted by the transmitter represents a signal selected by the transmitter from a plurality of candidate signals, and the received signal includes a combination of a phase shifted input data signal with a synchronization/pilot sequence, and wherein the plurality of pilot signals form a portion of the synchronization/pilot sequence;
• determining an estimate of a selective mapping (SLM) index, which identifies the synchronization/pilot sequence from a plurality of synchronization/pilot sequences;
• producing a corrected signal by applying corrections to the received signal based on estimated channel perturbations within the received signal, which estimated channel perturbations are determined based on the plurality of pilot signals, wherein producing the corrected signal is performed by applying the corrections to the received signal based the estimated channel perturbations within the received signal, wherein the estimated channel perturbations are determined based on the estimate of the SLM index and the plurality of pilot signals;
• and
• producing an output data symbol from the corrected signal.

A method comprising the steps of:

• receiving a received signal from a wireless communication channel, wherein the received signal represents a channel-affected version of a wireless signal that was transmitted by a transmitter, and wherein the wireless signal includes a guard band, data represented within a plurality of data-bearing subcarriers, and a plurality of pilot signals represented within a plurality of pilot subcarriers, wherein the plurality of pilot signals have variable pilot signal parameters selected from a group of parameters that includes pilot power and pilot spacing with respect to adjacent pilots, wherein subcarrier indices for the plurality of pilot subcarriers are unevenly-spaced, and are determined using a cubic parameterization of the pilot subcarriers in conjunction with a convex optimization algorithm to produce pilot signals that result in near-optimal channel estimate mean square error (MSE) performance;
• producing a corrected signal by applying corrections to the received signal based on estimated channel perturbations within the received signal, which estimated channel perturbations are determined based on the plurality of pilot signals;
• and
• producing an output data symbol from the corrected signal.

A method comprising the steps of:

• receiving a received signal from a wireless communication channel, wherein the received signal represents a channel-affected version of a wireless signal that was transmitted by a transmitter, and wherein the wireless signal includes a guard band, data represented within a plurality of data-bearing subcarriers, and a plurality of pilot signals represented within a plurality of pilot subcarriers, wherein the plurality of pilot signals have variable pilot signal parameters selected from a group of parameters that includes pilot power and pilot spacing with respect to adjacent pilots, wherein the wireless signal is an orthogonal frequency division multiplexed (OFDM) signal;
• producing a corrected signal by applying corrections to the received signal based on estimated channel perturbations within the received signal, which estimated channel perturbations are determined based on the plurality of pilot signals;
• and
• producing an output data symbol from the corrected signal.

A method comprising the steps of:

• receiving a received signal from a wireless communication channel, wherein the received signal represents a channel-affected version of a wireless signal that was transmitted by a transmitter, and wherein the wireless signal includes a guard band, data represented within a plurality of data-bearing subcarriers, and a plurality of pilot signals represented within a plurality of pilot subcarriers, wherein the plurality of pilot signals have variable pilot signal parameters selected from a group of parameters that includes pilot power and pilot spacing with respect to adjacent pilots, wherein the wireless signal is an orthogonal frequency division multiple access (OFDMA) signal;
• producing a corrected signal by applying corrections to the received signal based on estimated channel perturbations within the received signal, which estimated channel perturbations are determined based on the plurality of pilot signals;
• and
• producing an output data symbol from the corrected signal.

A method comprising the steps of:

• receiving a received signal from a wireless communication channel, wherein the received signal represents a channel-affected version of a wireless signal that was transmitted by a transmitter, and wherein the wireless signal includes a guard band, data represented within a plurality of data-bearing subcarriers, and a plurality of pilot signals represented within a plurality of pilot subcarriers, wherein the plurality of pilot signals have variable pilot signal parameters selected from a group of parameters that includes pilot power and pilot spacing with respect to adjacent pilots, wherein the wireless signal is wideband code division multiple access (W-CDMA) signal;
• producing a corrected signal by applying corrections to the received signal based on estimated channel perturbations within the received signal, which estimated channel perturbations are determined based on the plurality of pilot signals;
• and
• producing an output data symbol from the corrected signal.