An embedded system is described. The embedded system includes a processing circuit comprising Q processing units that can be operated in parallel. A memory is operably coupled to the processing circuit and includes at least input data. The processing circuit is configured to support an implementation of a non-power-of-2 fast Fourier transform of length N using a multiplication of at least two smaller FFTs of a respective first length N1 and second length N2, where N1 and N2 are whole numbers. The processing circuit is further configured to employ a customized instruction configured to perform an FFT operation of length less than Q using a first of the at least two smaller FFTs.

Methods and systems are provided that enable an OFDM transmitter to be used for transmitting conventional OFDM or a form of transformed OFDM. A technique is provided for transforming a coded and modulated sequence of samples prior to an IFFT that enables the transformed sequence of samples to be transmitted using conventional OFDM or transformed OFDM. The selection of a transform function for transforming the coded and modulated sequence of samples may be based on optimizing the transform function for particular operating conditions between the transmitter and receiver. In some embodiments of the invention OFDM and time transformed OFDM are multiplexed in time and/or frequency in a transmission frame. In some embodiments of the invention a pilot pattern is provided in which the pilot are sent using OFDM and data is sent using OFDM and/or transformed OFDM.

Frame formatting for communications within single user, multiple user, multiple access, and/or MIMO wireless communications. A signal is processed within a communication device using at least two respective downclocking ratios (e.g., a first downclocking ratio applied to a first portion of the signal such as a frame or packet extracted there from, a second downclocking ratio applied to a second portion of the signal). Alternatively, a signal is divided into more than two respective portions, and different respective downclocking ratios are applied to those different respective portions (e.g., a first downclocking ratio applied to a first portion of the signal, and so on up to an n-th downclocking ratio applied to an n-th portion of the signal). Some implementations apply a singular or common downclocking ratio to more than one portion of the signal (which may be contiguous/adjacent or non-contiguous/non-adjacent within the signal).

A method for adaptively-tuned digital self-interference cancellation includes generating a digital self-interference cancellation signal from a digital transmit signal based on a transform configuration; combining the digital self-interference cancellation signal with a receive signal to form a digital residue signal; generating a composite residue signal from the digital residue signal and the digital transmit signal; and updating the transform configuration based on the composite residue signal.

Disclosed herein is a broadcast signal receiver. The broadcast signal receiver according to an embodiment of the present invention includes a synchronization and demodulation module configured to perform detection and OFDM demodulation on a received broadcast signal, a frame parsing and deinterleaving module configured to parse and deinterleave the signal frame of the broadcast signal, a demapping and decoding module configured to convert the data of at least one Physical Layer Pipe (PLP) of the broadcast signal into a bit domain and to FEC-decode the PLP data, and an output processing module configured to receive the data of the at least one PLP and to output the received data in a data stream form.

An array-based Compressed sensing Receiver Architecture (ACRA) includes an antenna array with two or more antennas connected to two or more ADCs that are clocked at two or more different sampling rates below the Nyquist rate of the incident signals. Comparison of the individual aliased outputs of the ADCs allows for estimation of signal component characteristics, including signal bandwidth, center frequency, and direction-of-arrival (DoA). Multiple digital signal processing (DSP) techniques, such as sparse fast Fourier transform (sFFT), can be employed depending on the type of detection or estimation.

An orthogonal frequency division multiplexing (OFDM) transmission system is provided which includes a data processing unit which generates a transmission signal using a plurality of tones including a reserved tone, a storage unit which stores Peak Reduction Kernel information according to the type of data symbol, and a compensation unit which retrieves the Peak Reduction Kernel information according to the type of data symbol from the storage unit and causes the retrieved information to be carried by the reserved tone included in the transmission signal. Therefore, a Peak-to-Average Power Ratio (PAPR) can be efficiently compensated.

The present invention relates to an orthogonal frequency division multiplexing wireless local area network (LAN) transmitting/receiving system for providing expanded service coverage, and a method thereof. A first OFDM modulation is performed for an even-numbered time, and a second OFDM modulation is performed for an odd-numbered time. A transmitting frame including a plurality of signal fields according to the first and second OFDM modulation is transmitted. The receiving system determines whether a signal field is repeatedly generated in the frame. If the signal field is not repeatedly generated, corresponding demodulation is performed. If repeatedly performed, the signal field is demodulated by using first bit allocation information and second bit allocation information having a value of the first bit allocation information. A data field is demodulated according to the demodulated signal field.

A method of determining the presence of a secondary carrier signal in a time-domain sum-signal including a primary carrier signal is disclosed, the method comprising: transforming the sum-signal into the frequency domain; extracting at least one peak corresponding to a heterodyne tone from the transformed sum-signal; determining the presence of a secondary carrier signal in the sum-signal based on said at least one peak. A corresponding apparatus is also disclosed.

Methods and systems are provided that enable an OFDM transmitter to be used for transmitting conventional OFDM or a form of transformed OFDM. A technique is provided for transforming a coded and modulated sequence of samples prior to an IFFT that enables the transformed sequence of samples to be transmitted using conventional OFDM or transformed OFDM. The selection of a transform function for transforming the coded and modulated sequence of samples may be based on optimizing the transform function for particular operating conditions between the transmitter and receiver. In some embodiments of the invention OFDM and time transformed OFDM are multiplexed in time and/or frequency in a transmission frame. In some embodiments of the invention a pilot pattern is provided in which the pilot are sent using OFDM and data is sent using OFDM and/or transformed OFDM.