Abstract: Systems and methods for using non-crystal-based reference oscillators in the transmission and reception of frequency-modulated signals are disclosed. To protect against intrusion on neighboring designated frequency bands, guard bands, having a collective width greater than the total expected error based on the contribution of the frequency error from the non-crystal-based oscillators in the transmitter and/or receiver, can be designated. To protect against inter-channel interference within a designated frequency band, transmitters and receivers can include static sub-bandwidths wider than any possible total frequency error, such that it would be impossible for a transmitter or receiver to attempt to communicate on an unintended sub-band.

Abstract: Systems and techniques relating to wireless communications are described.

Abstract: Systems, methods, and other embodiments associated with preamble detection based on repeated preamble codes are described. According to one embodiment, an apparatus is provided that wirelessly receives a signal and calculates a differential output corresponding to a multiplication of the signal and a delayed version of the signal. A cross correlation is performed between the differential output and a known preamble pattern to produce a cross correlation output. One or more peaks are detected in the cross correlation. The detected peaks are used in subsequent processing to detect the known preamble pattern in the wirelessly received signal.

Abstract: A radio frequency transmitting system which includes first and second amplifiers, a power detector, and a calibration module. The first amplifier amplifies an input signal to generate an amplified signal in accordance with a programmable gain. The second amplifier transmits an output signal based on the amplified signal. The output signal is transmitted at a particular power by the second amplifier. The power detector measures the particular power at which the output signal is transmitted by the second amplifier. The calibration module adjusts the programmable gain of the first amplifier by a calibration offset so that the particular power measurement matches a predetermined power. The calibration module includes offset generation modules that each generate a respective calibration offset candidate based on the particular power measurement. The calibration module also includes a selection module that selects, based on the predetermined power, one of the calibration offset candidates as the calibration offset.

Abstract: Systems and techniques relating to wireless communications are described. A described technique includes receiving information that is indicative of a wireless communication signal transmitted by a wireless communication device, the wireless communication signal having been generated based on a spreading sequence and a known preamble; determining, based on the received information and the known preamble, an estimation of a first frequency offset using two or more locations for encoding elements associated with the spreading sequence; determining, based on the received information, the known preamble, and the first frequency offset, an estimation of a second frequency offset using two or more locations for symbols associated with the known preamble, the second frequency offset being different from the first frequency offset; and processing the received information based on a combination of the first frequency offset and the second frequency offset.

Abstract: A radio frequency transmitting system includes a programmable amplifier, a power amplifier, a power detector, and a calibration module. The programmable amplifier is configured to amplify an input signal to generate an amplified signal. The power amplifier is configured to output a transmit signal in response to the amplified signal. The transmit signal has a transmit power. The power detector is configured to generate a power measurement in response to the transmit power. The calibration module is configured to implement a plurality of feedback loops to adjust a gain of the programmable amplifier in response to a difference between the power measurement and a desired transmit power. The calibration module is configured to select one of the plurality of feedback loops in response to the desired transmit power.

Abstract: Systems and methods for using non-crystal-based reference oscillators in the transmission and reception of frequency-modulated signals are disclosed. To protect against intrusion on neighboring designated frequency bands, guard bands, having a collective width greater than the total expected error based on the contribution of the frequency error from the non-crystal-based oscillators in the transmitter and/or receiver, can be designated. To protect against inter-channel interference within a designated frequency band, transmitters and receivers can include static sub-bandwidths wider than any possible total frequency error, such that it would be impossible for a transmitter or receiver to attempt to communicate on an unintended sub-band.

Abstract: Systems, methods, and other embodiments associated with preamble detection based on repeated preamble codes are described. According to one embodiment, an apparatus is provided that wirelessly receives a signal and calculates a differential output corresponding to a multiplication of the signal and a delayed version of the signal. A cross correlation is performed between the differential output and a known preamble pattern to produce a cross correlation output. A moving average calculation is performed on the cross correlation output to produce an average cross correlation. One or more peaks are detected in the average cross correlation when the average cross correlation has an amplitude greater than a threshold. When the one or more detected peaks meets predetermined criteria, the apparatus provides information about at least one of the detected peaks for subsequent signal processing.

Abstract: Systems and techniques relating to wireless communications are described.

Abstract: In this invention compare circuitry is integrated into a serial shift register which can detect a bit pattern of any length with only the delay of three circuits being added to the shift of the last bit in the bit pattern. The circuitry is connected to operate either is a shift register or as a comparator for an N element bit pattern. Between adjacent registers in the shift register is a MUX used to select compare or shift register operation. An exclusive NOR circuit performs the compare between bits of the serial bit stream and reference bits of the pattern to be protected. An AND circuit accumulates the compare of a particular stage with the compare with the preceding stage. In the last stage the AND circuit provide an accumulated compare result of the preceding number of bit equaling in length the length of the bit pattern for which the compare is being performed.