Abstract: A range profile digitization circuit for converting a repeating analog input signal into a time series of digital amplitude values, the converter comprising: a signal quantizer arranged to receive the analog input signal and a threshold input and arranged to output a binary value quantized output signal based on a comparison of the input signal with the threshold signal; a plurality of samplers each arranged to sample and hold its input signal upon receipt of a trigger signal; and for each sampler: a plurality of decoders and a demultiplexer arranged to receive an output from the sampler and pass it to a selected one of said decoders based on a selector input. With a plurality of decoders associated with each of the samplers, each sampler can be re-used during the building up of the range profile.

Abstract: A range profile digitization circuit for converting a repeating analog input signal into a time series of digital amplitude values, the converter comprising: a signal quantizer arranged to receive the analog input signal and a threshold input and arranged to output a binary value quantized output signal based on a comparison of the input signal with the threshold signal; a plurality of samplers each arranged to sample and hold its input signal upon receipt of a trigger signal; and for each sampler: a plurality of decoders and a demultiplexer arranged to receive an output from the sampler and pass it to a selected one of said decoders based on a selector input. With a plurality of decoders associated with each of the samplers, each sampler can be re-used during the building up of the range profile.

Abstract: According to a first aspect, a pulsed radar comprises a transmitter; wherein the pulsed radar is arranged to generate a string of binary values; wherein the transmitter comprises a pulse generator arranged to generate a pulse signal comprising a series of transmit pulses with polarities determined in accordance with the string of binary values; wherein a first substring comprises a first series of values; wherein a second substring comprises a second series of values; wherein the second substring is different from the first substring; and wherein each value in the second series of values is either the same as or different from the corresponding value in the first series of values according to a repeating pattern; and wherein the string of binary values comprises at least the first substring and the second substring concatenated together and each optionally being reversed before concatenation.

Abstract: A delay measurement apparatus for measuring a delay unit comprising: a clock; clock counter; a digital signal source that is uncorrelated with the clock; a first detector arranged to detect transitions of the digital signal entering the delay unit; a first accumulator arranged to accumulate the current clock counter value based on the output of the first detector; a second detector arranged to detect transitions of the digital signal exiting the delay unit; a second accumulator arranged to accumulate the current clock counter value based on the output of the second detector; a measurement counter arranged to count the number of transitions of the digital signal passing through the delay unit; and a calculation device arranged to calculate an average number of clock cycles that elapse while a transition of the digital signal passes through the delay unit based on the first accumulator, the second accumulator and the measurement counter.

Abstract: According to a first aspect, a pulsed radar comprises a transmitter; wherein the pulsed radar is arranged to generate a string of binary values; wherein the transmitter comprises a pulse generator arranged to generate a pulse signal comprising a series of transmit pulses with polarities determined in accordance with the string of binary values; wherein a first substring comprises a first series of values; wherein a second substring comprises a second series of values; wherein the second substring is different from the first substring; and wherein each value in the second series of values is either the same as or different from the corresponding value in the first series of values according to a repeating pattern; and wherein the string of binary values comprises at least the first substring and the second substring concatenated together and each optionally being reversed before concatenation.

Abstract: A range profile digitization circuit for converting a repeating analog input signal into a time series of digital amplitude values, the converter comprising: a signal quantizer arranged to receive the analog input signal and a threshold input and arranged to output a binary value quantized output signal based on a comparison of the input signal with the threshold signal; a plurality of samplers each arranged to sample and hold its input signal upon receipt of a trigger signal; and for each sampler: a plurality of decoders and a demultiplexer arranged to receive an output from the sampler and pass it to a selected one of said decoders based on a selector input. With a plurality of decoders associated with each of the samplers, each sampler can be re-used during the building up of the range profile.

Abstract: A delay measurement apparatus for measuring a delay unit comprising: a clock; clock counter; a digital signal source that is uncorrelated with the clock; a first detector arranged to detect transitions of the digital signal entering the delay unit; a first accumulator arranged to accumulate the current clock counter value based on the output of the first detector; a second detector arranged to detect transitions of the digital signal exiting the delay unit; a second accumulator arranged to accumulate the current clock counter value based on the output of the second detector; a measurement counter arranged to count the number of transitions of the digital signal passing through the delay unit; and a calculation device arranged to calculate an average number of clock cycles that elapse while a transition of the digital signal passes through the delay unit based on the first accumulator, the second accumulator and the measurement counter.

Abstract: A tunable delay unit and methods of tuning are provided, comprising a plurality of first delay elements and a plurality of first delay element taps between the first delay elements, wherein the first delay element taps are inputs to a first multiplexer and wherein the output of the first multiplexer is selected from among the inputs according to a first tap select input, further comprising a plurality of second delay elements connected in series to the output of the first multiplexer and a plurality of second delay element taps between the second delay elements, wherein the second delay element taps are inputs to a second multiplexer and wherein the output of the second multiplexer is selected from among the inputs according to a second tap select input, the output of the second multiplexer forming the output of the programmable delay unit. The programmable delay unit provides for highly accurate calibration of timed circuits, in particular delay lines.

Abstract: A pulse generator comprising: an input for receiving a trigger; an output node for outputting a signal; a delay line comprising one or more delay units and a plurality of taps; one or more pull-up devices each connected to the output node for increasing the output voltage on the output node; and/or one or more pull-down devices each connected to the output node for decreasing the output voltage on the output node; wherein the taps of the delay line are operably connected to the pull-up and/or pull-down devices such that a trigger passing along the delay line activates one or more of the pull-up and/or one or more of the pull-down devices more than once. Re-use of the pull-up and/or pull-down devices enables longer and more complex pulse shapes, such as high-order Gaussian pulse shapes to be produced while keeping the number of components low, thus reducing chip area, power requirements and parasitic capacitance.

Abstract: There is provided a continuous time cross-correlator comprising: a quantizer for quantizing the incoming signal into discrete levels; a delay line comprising one or more delay units separating a plurality of delay line taps; for each of said delay line taps, a comparator for comparing the signal level of the delay line tap with a correlation value; a continuous time counter for taking the outputs of the plurality of comparators as its inputs, counting the results of the comparisons and outputting the results of the comparisons; and an output comparator for comparing the counter output with a threshold value. The cross-correlator provides for high speed continuous time cross-correlation with low power consumption and a small chip area. Methods of continuous time cross correlation are also provided.

Abstract: A tunable delay unit and methods of tuning are provided, comprising a plurality of first delay elements and a plurality of first delay element taps between the first delay elements, wherein the first delay element taps are inputs to a first multiplexer and wherein the output of the first multiplexer is selected from among the inputs according to a first tap select input, further comprising a plurality of second delay elements connected in series to the output of the first multiplexer and a plurality of second delay element taps between the second delay elements, wherein the second delay element taps are inputs to a second multiplexer and wherein the output of the second multiplexer is selected from among the inputs according to a second tap select input, the output of the second multiplexer forming the output of the programmable delay unit. The programmable delay unit provides for highly accurate calibration of timed circuits, in particular delay lines.

Abstract: A pulse generator comprising: an input for receiving a trigger; an output node for outputting a signal; a delay line comprising one or more delay units and a plurality of taps; one or more pull-up devices each connected to the output node for increasing the output voltage on the output node; and/or one or more pull-down devices each connected to the output node for decreasing the output voltage on the output node; wherein the taps of the delay line are operably connected to the pull-up and/or pull-down devices such that a trigger passing along the delay line activates one or more of the pull-up and/or one or more of the pull-down devices more than once. Re-use of the pull-up and/or pull-down devices enables longer and more complex pulse shapes, such as high-order Gaussian pulse shapes to be produced while keeping the number of components low, thus reducing chip area, power requirements and parasitic capacitance.

Abstract: There is provided a continuous time cross-correlator comprising: a quantizer for quantizing the incoming signal into discrete levels; a delay line comprising one or more delay units separating a plurality of delay line taps; for each of said delay line taps, a comparator for comparing the signal level of the delay line tap with a correlation value; a continuous time counter for taking the outputs of the plurality of comparators as its inputs, counting the results of the comparisons and outputting the results of the comparisons; and an output comparator for comparing the counter output with a threshold value. The cross-correlator provides for high speed continuous time cross-correlation with low power consumption and a small chip area. Methods of continuous time cross correlation are also provided.