A system and method for generating communications waveforms that can operate in congested frequency spaces and in applications in which the receiver is moving with respect to the transmitter is provided. In one or more examples, each symbol to be encoded and transmitted is converted into a sequence of frequency chirps. The sequence of frequencies used by the sequence of chirps is based on the symbol that is to be encoded. Each chirp can have a center frequency, and the frequency can be swept over the duration of the chirp. In this way each chirp can have a varying frequency over the duration of the chirp, but the phase of the chirp can be continuous throughout the duration of the chirp. The bandwidth and sweep rate of the chirp can be based on the expected maximum velocity of the receiver and the transmitter relative to one another.

A spread-spectrum transmitter is disclosed. The transmitter includes a modulator configured to produce an intermediate frequency signal, a frequency shifter configured to shift the intermediate frequency factor by a first factor, and a local oscillator (LO) configured to generate a LO signal. The transmitter further includes a ramp signal generator configured to determine the value of the first factor and a second factor, is configured to transmit the value of the factor to the frequency shifter, is configured to transmit the value of the second factor to the LO, where the frequency of the intermediate frequency signal shifted by the first factor is shifted synchronously with the frequency of the LO signal shifted by the second factor. The transmitter includes a mixer configured to mix the shifted intermediate frequency with the shifted LO signal that has been shifted by the second factor, producing a spread leaked LO signal.

A spread-spectrum transmitter is disclosed. The transmitter includes a modulator configured to produce an intermediate frequency signal, a frequency shifter configured to shift the intermediate frequency factor by a first factor, and a local oscillator (LO) configured to generate a LO signal. The transmitter further includes a ramp signal generator configured to determine the value of the first factor and a second factor, is configured to transmit the value of the factor to the frequency shifter, is configured to transmit the value of the second factor to the LO, where the frequency of the intermediate frequency signal shifted by the first factor is shifted synchronously with the frequency of the LO signal shifted by the second factor. The transmitter includes a mixer configured to mix the shifted intermediate frequency with the shifted LO signal that has been shifted by the second factor, producing a spread leaked LO signal.

A wireless networking system is provided. The wireless networking system includes a base station device including processing circuitry configured to detect a transmission rate from a portion of a preamble of an incoming packet transmission signal and adapt a radio configuration to receive a remainder of the incoming packet transmission signal at the transmission rate.

A method for transmitting a sounding reference signal (SRS) by a terminal comprises the steps of: receiving, from a base station, the number of SRS repetition symbols, group hopping patterns, sequence hopping patterns, pattern selection information, and hopping selection information; generating an SRS sequence by applying a group hopping pattern and a sequence hopping pattern selected according to the pattern selection information and the hopping selection information; and transmitting the SRS on the basis of the SRS sequence, wherein the group hopping patterns include a group hopping pattern calculated using the number of SRS repetition symbols, the sequence hopping patterns include a sequence hopping pattern calculated using the number of SRS repetition symbols, and the hopping selection information selects whether to activate group hopping and sequence hopping.

A method for transmitting a sounding reference signal (SRS) by a terminal comprises the steps of: receiving, from a base station, the number of SRS repetition symbols, group hopping patterns, sequence hopping patterns, pattern selection information, and hopping selection information; generating an SRS sequence by applying a group hopping pattern and a sequence hopping pattern selected according to the pattern selection information and the hopping selection information; and transmitting the SRS on the basis of the SRS sequence, wherein the group hopping patterns include a group hopping pattern calculated using the number of SRS repetition symbols, the sequence hopping patterns include a sequence hopping pattern calculated using the number of SRS repetition symbols, and the hopping selection information selects whether to activate group hopping and sequence hopping.

A wireless networking system is provided. The wireless networking system includes a base station device including processing circuitry configured to detect a transmission rate from a portion of a preamble of an incoming packet transmission signal and adapt a radio configuration to receive a remainder of the incoming packet transmission signal at the transmission rate.

According to methods of performing a passive inter-modulation distortion (“PID”) test, a first excitation signal and a second excitation signal are applied to a device under test, where at least one of the first and second excitation signals is a spread spectrum excitation signal. An output signal is received that includes a PID signal generated from mixing of the first and second excitation signals. At least a portion of the output signal is de-spread. A characteristic of the PID signal may then be measured.

A system may include a first radio comprising a first radio processor, a first radio modem, and a first radio transmitter configured to transmit non-hopping transmissions and hopping transmissions. The system may further include a second radio comprising a second radio processor, a second radio modem, and a second radio hopping receiver, wherein the second radio hopping receiver is a non-staring second radio receiver. The first radio may be configured to: receive a message and a destination for the message, the destination being the second radio; upon a determination that the destination has a non-staring receiver, store the message; determine a time interval start time for a cyclical hop pattern associated with the second radio; output the message from the memory to the first radio modem; output the message from the first radio modem to the first radio transmitter; and/or transmit the message to the second radio.

Embodiments of the present invention provide a participant of a communication system, wherein the communication system communicates wirelessly in a frequency used by a plurality of communication systems, wherein the participant is configured to transmit data uncoordinatedly with respect to other participants and/or a base station of the communication system, wherein the participant is configured to receive a synchronization data packet of a point-to-multipoint data transfer of the base station of the communication system, wherein the synchronization data packet is transferred in a frequency range of the frequency band of the communication system that is specified or known to the participant, wherein the participant is configured to receive, on the basis of the synchronization data packet, a payload data packet of the point-to-multipoint data transfer that is referenced in time and/or frequency to the synchronization data packet.