Abstract: A microcontroller-based system for measuring the impedance of a device under test (DUT), responsive to a square wave stimulus, includes parallel stimulus signal paths, selectable by a switch, that can correspond to different stimulus frequency ranges. At least one of the paths includes an off-chip PLL and integer divider circuit to modify the frequency of the stimulus. A discrete Fourier transform executed by a processor is used to determine the impedance of the DUT at the stimulus frequency. Multiple frequencies can be analyzed at the same time by using a summation circuit and/or by analyzing odd harmonics of the stimulus frequency.

Abstract: Embodiments of the present disclosure provide a transmitter, a receiver and methods of operating a transmitter or a receiver. In one embodiment, the transmitter is for use with a base station and includes a primary module configured to provide a primary synchronization signal. The transmitter also includes a secondary mapping module configured to provide a secondary synchronization signal derived from two sequences taken from a same set of N sequences and indexed by an index pair (S1, S2) with S1 and S2 ranging from zero to N?1, wherein the index pair (S1, S2) is contained in a mapped set of index pairs corresponding to the same set of N sequences that defines a cell identity group. Additionally, the transmitter further includes a transmit module configured to transmit the primary and secondary synchronization signals.

Abstract: Embodiments of the present disclosure provide a transmitter, a receiver and methods of operating a transmitter and a receiver. In one embodiment, the transmitter includes a synchronization unit configured to provide a primary synchronization signal and a secondary synchronization signal having first and second segments. The transmitter also includes a secondary scrambling unit configured to provide a scrambled secondary synchronization signal, wherein scrambling agents for the first and second segments are derived from a primary synchronization sequence of the primary synchronization signal. The secondary scrambling unit is further configured to provide an additional scrambling of one of the first and second segments, wherein a second scrambling agent is derived from the remaining segment of a secondary synchronization sequence of the secondary synchronization signal.

Abstract: Embodiments of the present disclosure provide a transmitter, a receiver and methods of operating a transmitter or a receiver. In one embodiment, the transmitter is for use with a base station and includes a primary module configured to provide a primary synchronization signal. The transmitter also includes a secondary mapping module configured to provide a secondary synchronization signal derived from two sequences taken from a same set of N sequences and indexed by an index pair (S1, S2) with S1 and S2 ranging from zero to N?1, wherein the index pair (S1, S2) is contained in a mapped set of index pairs corresponding to the same set of N sequences that defines a cell identity group. Additionally, the transmitter further includes a transmit module configured to transmit the primary and secondary synchronization signals.

Abstract: An ultrasonic communication circuit is disclosed. The circuit includes an ultrasonic transmitter arranged to transmit a training signal having a frequency to a remote transceiver over an ultrasonic communication channel. An ultrasonic receiver is arranged to receive information from the remote transceiver in response to the training signal. The ultrasonic transmitter is arranged to transmit a data signal to the remote transceiver. The data signal has a duty cycle determined by the information.

Abstract: Embodiments of the present disclosure provide a transmitter, a receiver and methods of operating a transmitter and a receiver. In one embodiment, the transmitter includes a synchronization unit configured to provide a primary synchronization signal and a secondary synchronization signal having first and second segments. The transmitter also includes a secondary scrambling unit configured to provide a scrambled secondary synchronization signal, wherein scrambling agents for the first and second segments are derived from a primary synchronization sequence of the primary synchronization signal. The secondary scrambling unit is further configured to provide an additional scrambling of one of the first and second segments, wherein a second scrambling agent is derived from the remaining segment of a secondary synchronization sequence of the secondary synchronization signal.

Abstract: An ultrasonic communication circuit is disclosed. The circuit includes an ultrasonic transmitter arranged to transmit a training signal having a frequency to a remote transceiver over an ultrasonic communication channel. An ultrasonic receiver is arranged to receive information from the remote transceiver in response to the training signal. The ultrasonic transmitter is arranged to transmit a data signal to the remote transceiver. The data signal has a duty cycle determined by the information.

Abstract: A method of encoding a plurality of data signals is disclosed. The method includes selecting a set of M ultrasonic frequencies, wherein each of the M ultrasonic frequencies differs from an adjacent frequency by at least a first frequency spacing, and wherein M is a positive integer. An encoder receives the plurality of data signals. Each of the plurality of data signals is encoded by a respective set of Q of the M ultrasonic frequencies, wherein Q is a positive integer less than M. A minimum frequency separation between any pair of the Q ultrasonic frequencies of any respective set is greater than the first frequency spacing.

Abstract: An apparatus for preventing a relay attack that includes a microcontroller, a receiver, and a transmitter. The receiver is configured to receive a challenge message from a verifier. The challenge message has a challenge message frequency at a first challenge message frequency during a first time slot. The transmitter is configured to transmit a response message to the verifier. The response message has a response message frequency at a first response message frequency during the first time slot. The first response message frequency is different than the first challenge message frequency. The challenge message frequency is at a second challenge message frequency and the response message frequency is at a second response message frequency during a second time slit. The second challenge message frequency is different than the second response message frequency.

Abstract: This invention pertains to a method by which the frequency and the modulation characteristics of a wire or wirelessly transmitted signal can be identified in a matter of milliseconds with significantly higher speed and accuracy than with existing or prior art receivers and spectrum analyzers, without erroneous image signals. Such signals can be then demodulated and decisions made based upon the demodulated data. The system then can be reconfigured to act as a transmit-receive module, with the transmit frequency enabled to address many different applications. This has applications in, terrestrial and satellite communications, and defense.

Abstract: A method of encoding a data signal is disclosed. The method includes selecting a set of M ultrasonic frequencies, wherein each of the M ultrasonic frequencies differs from an adjacent frequency by at least a first frequency spacing, and wherein M is a positive integer. The method further includes forming a trellis matrix and encoding the data signal with the trellis matrix to form a set of Q of the M ultrasonic frequencies, wherein Q is a positive integer less than M, and wherein a minimum frequency separation between any pair of the Q frequencies of the set is greater than the first frequency spacing.

Abstract: In one embodiment, a transmitter includes a binary sequence generator unit configured to provide a sequence of reference signal bits, wherein the sequence is an inseparable function of a cell identification parameter, a cyclic prefix mode corresponding to the transmitter and one or more time indices of the sequence. The transmitter also include a mapping unit that transforms the sequence of reference signal bits into a complex reference signal, and a transmit unit configured to transmit the complex reference signal. In another embodiment, a receiver includes a receive unit configured to receive a complex reference signal and a reference signal decoder unit configured to detect a sequence of reference signal bits from the complex reference signal, wherein the sequence is an inseparable function of a cell identification parameter, a cyclic prefix mode corresponding to a transmitter and one or more time indices of the sequence.

Abstract: Embodiments of the present disclosure provide a transmitter, a receiver and methods of operating a transmitter and a receiver. In one embodiment, the transmitter includes a synchronization unit configured to provide a primary synchronization signal and a secondary synchronization signal having first and second segments. The transmitter also includes a secondary scrambling unit configured to provide a scrambled secondary synchronization signal, wherein scrambling agents for the first and second segments are derived from a primary synchronization sequence of the primary synchronization signal. The secondary scrambling unit is further configured to provide an additional scrambling of one of the first and second segments, wherein a second scrambling agent is derived from the remaining segment of a secondary synchronization sequence of the secondary synchronization signal.

Abstract: Embodiments of the present disclosure provide a transmitter, a receiver and methods of operating a transmitter and a receiver. In one embodiment, the transmitter includes a synchronization unit configured to provide a primary synchronization signal and a secondary synchronization signal having first and second segments. The transmitter also includes a secondary scrambling unit configured to provide a scrambled secondary synchronization signal, wherein scrambling agents for the first and second segments are derived from a primary synchronization sequence of the primary synchronization signal. The secondary scrambling unit is further configured to provide an additional scrambling of one of the first and second segments, wherein a second scrambling agent is derived from the remaining segment of a secondary synchronization sequence of the secondary synchronization signal.

Abstract: In one embodiment, a transmitter includes a binary sequence generator unit configured to provide a sequence of reference signal bits, wherein the sequence is an inseparable function of a cell identification parameter, a cyclic prefix mode corresponding to the transmitter and one or more time indices of the sequence. The transmitter also include a mapping unit that transforms the sequence of reference signal bits into a complex reference signal, and a transmit unit configured to transmit the complex reference signal. In another embodiment, a receiver includes a receive unit configured to receive a complex reference signal and a reference signal decoder unit configured to detect a sequence of reference signal bits from the complex reference signal, wherein the sequence is an inseparable function of a cell identification parameter, a cyclic prefix mode corresponding to a transmitter and one or more time indices of the sequence.

Abstract: The present disclosure provides a receiver, a transmitter and methods of operating a receiver or a transmitter. In one embodiment, the receiver includes a receive unit configured to receive transmissions from multiple antennas. The receiver also includes a rank feedback unit configured to feed back a transmission rank selection, wherein the transmission rank selection corresponds to a transmission rank feedback reduction scheme. The receiver further includes a precoding feedback unit configured to feed back a preceding matrix selection, wherein the preceding matrix selection corresponds to a preceding matrix feedback reduction schemes.

Abstract: Embodiments of the present disclosure provide a transmitter, a receiver and methods of operating a transmitter and a receiver. In one embodiment, the transmitter includes a synchronization unit configured to provide a primary synchronization signal and a secondary synchronization signal having first and second segments. The transmitter also includes a secondary scrambling unit configured to provide a scrambled secondary synchronization signal, wherein scrambling agents for the first and second segments are derived from a primary synchronization sequence of the primary synchronization signal. The secondary scrambling unit is further configured to provide an additional scrambling of one of the first and second segments, wherein a second scrambling agent is derived from the remaining segment of a secondary synchronization sequence of the secondary synchronization signal.

Abstract: This invention describes a method by which the frequency and the modulation characteristics of a wire or wirelessly transmitted signal can be identified in a matter of milliseconds with significantly higher speed and accuracy than with existing or prior art receivers and spectrum analyzers, without erroneous image signals. Such signals can be then demodulated and decisions made based upon the demodulated data. The system then can be reconfigured to act as a transmit-receive module, with the transmit frequency enabled to address many different applications. This has applications in, terrestrial and satellite communications, and defense.

Abstract: Various wireless precoding systems and methods are presented. In some embodiments, a wireless transmitter comprises an antenna precoding block, a transform block, and multiple transmit antennas. The antenna precoding block receives frequency coefficients from multiple data streams and distributes the frequency coefficients across multiple transmit signals in accordance with frequency-dependent matrices. The transform block transforms the preceded frequency coefficients into multiple time domain transmit signals to be transmitted by the multiple antennas. The frequency coefficients from multiple data streams may be partitioned into tone groups, and all the frequency coefficients from a given tone group may be redistributed in accordance with a single matrix for that tone group. In some implementations, the frequency coefficients within a tone group for a given data stream may also be precoded. In some alternative embodiments, tone group preceding may be employed in a single channel system.

Abstract: The present disclosure provides a receiver, a transmitter and methods of operating a receiver or a transmitter. In one embodiment, the receiver includes a receive unit configured to receive transmissions from multiple antennas. The receiver also includes a rank feedback unit configured to feed back a transmission rank selection, wherein the transmission rank selection corresponds to a transmission rank feedback reduction scheme. The receiver further includes a precoding feedback unit configured to feed back a preceding matrix selection, wherein the preceding matrix selection corresponds to a preceding matrix feedback reduction schemes.