Abstract:
An agile transceiver including a receiver channel that includes an input, a coarse tracking filter coupled to the input, the coarse tracking filter having a set of at least two bandpass filters for filtering signals from the input into at least two coarse pass bands, a mixer coupled to an output of the coarse tracking filter, a selected local oscillator coupled to the mixer for mixing with the output of the coarse tracking filter and shifting a desired coarse pass band to near a base band, a fine tracking filter for filtering the shifted and desired coarse pass band to a fine pass band, and a band pass ΣΔ demodulator for converting signals in the fine pass band from analog into digital. The agile transceiver may include a corresponding transmitter channel.
Abstract:
A Delta-Sigma modulator architecture is disclosed that uses interleaving and dynamic matching algorithms to address the needs of multi-mode, multi-band high bandwidth transmitters. The proposed architecture also supports a novel software defined transmitter architecture based on an interleaved Delta-Sigma modulator to generate RF signals. The proposed architecture leverages interleaving concepts to relax subcomponent clock rates without changing the effective oversampling ratio, thus, making it easier to reach aggressive dynamic range goals across wider bandwidths at higher frequencies. The DEM algorithm helps to randomize mismatch errors across all interleaved paths and improves substantially the signal-to-noise ratio. Additionally, a tunable bandpass filter can be added to reject out-of-band emissions.
Abstract:
A Delta-Sigma modulator architecture is disclosed that uses interleaving and dynamic matching algorithms to address the needs of multi-mode, multi-band high bandwidth transmitters. The proposed architecture also supports a novel software defined transmitter architecture based on an interleaved Delta-Sigma modulator to generate RF signals. The proposed architecture leverages interleaving concepts to relax subcomponent clock rates without changing the effective oversampling ratio, thus, making it easier to reach aggressive dynamic range goals across wider bandwidths at higher frequencies. The DEM algorithm helps to randomize mismatch errors across all interleaved paths and improves substantially the signal-to-noise ratio. Additionally, a tunable bandpass filter can be added to reject out-of-band emissions.
Abstract:
An agile transceiver including a receiver channel that includes an input, a coarse tracking filter coupled to the input, the coarse tracking filter having a set of at least two bandpass filters for filtering signals from the input into at least two coarse pass bands, a mixer coupled to an output of the coarse tracking filter, a selected local oscillator coupled to the mixer for mixing with the output of the coarse tracking filter and shifting a desired coarse pass band to near a base band, a fine tracking filter for filtering the shifted and desired coarse pass band to a fine pass band, and a band pass ΣΔ demodulator for converting signals in the fine pass band from analog into digital. The agile transceiver may include a corresponding transmitter channel.
Abstract:
An asynchronous pulse domain to synchronous digital domain converter for converting pulse domain signals in an input asynchronous pulse domain data stream to synchronous digital domain signals in a data output stream. The converter comprises a plurality of counters arranged in a ring configuration with only one counter in the ring being responsive at any given time to positive and negative going pulses in the input asynchronous pulse domain data stream, each counter, when so responsive, counting a number of time units between either (i) a positive going pulse and an immediately following negative going pulse or (ii) a negative going pulse and an immediately following positive going pulse, the counts of the counters when so responsive being synchronously converted to synchronous digital domain signals in the data output stream. The disclosed asynchronous pulse domain to synchronous digital domain converter can be used with spike domain signals if desired.
Abstract:
A radar system in which Coded Aperture Radar processing is performed on received radar signals reflected by one or more objects in a field of view which reflect a transmitted signal which covers a field of view with K sweeps and each sweep including Q frequency changes. For Type II CAR, the transmitted signal also includes N modulated codes per frequency step. The received radar signals are modulated by a plurality of binary modulators the results of which are applied to a mixer. The output of the mixer, for one acquisition results in a set of Q·K (for Type I CAR) or Q·K·N (for Type II CAR) complex data samples, is distributed among a number of digital channels, each corresponding to a desired beam direction. For each channel, the complex digital samples are multiplied, sample by sample, by a complex signal mask that is different for each channel.
Abstract:
A pulse domain 1 to 2N demultiplexer has a (i) pair of N stage counters each of which is responsive to an incoming pulse train in the pulse domain, one of the counters being responsive to leading edges of the pulses in the incoming pulse train and the other one of the counters being responsive to trailing edges of the pulses in the incoming pulse train and (ii) a control logic responsive to the states through which the pair of counters count, the control logic including 2N gate arrangements, each of the 2N gate arrangements generating a output signal of the pulse domain 1 to 2N demultiplexer.