Abstract: A pulse generator comprising: a first signal generating arm comprising a first inductor and a plurality of switching elements, each arranged to draw current through the first inductor; and a controller arranged to activate the plurality of switching elements in a predetermined sequence so as to generate a predetermined pulse waveform at a pulse generator output. The switching elements of the signal generating arm and the inductor together form a pulse synthesizer that takes the signal from the controller and uses it to synthesize an output pulse. Compared with conventional transmitter architectures, the functions of the upconversion mixer, the DAC, and the power amplifier are all performed by a single simplified circuit. This is both area efficient and power efficient.

Abstract: A pulse generator comprising: a first signal generating arm comprising a first inductor and a plurality of switching elements, each arranged to draw current through the first inductor; and a controller arranged to activate the plurality of switching elements in a predetermined sequence so as to generate a predetermined pulse waveform at a pulse generator output. The switching elements of the signal generating arm and the inductor together form a pulse synthesizer that takes the signal from the controller and uses it to synthesize an output pulse. Compared with conventional transmitter architectures, the functions of the upconversion mixer, the DAC, and the power amplifier are all performed by a single simplified circuit. This is both area efficient and power efficient.

Abstract: A pulse generator comprising: a first signal generating arm comprising a first inductor and a plurality of switching elements, each arranged to draw current through the first inductor; and a controller arranged to activate the plurality of switching elements in a predetermined sequence so as to generate a predetermined pulse waveform at a pulse generator output. The switching elements of the signal generating arm and the inductor together form a pulse synthesizer that takes the signal from the controller and uses it to synthesize an output pulse. Compared with conventional transmitter architectures, the functions of the upconversion mixer, the DAC, and the power amplifier are all performed by a single simplified circuit. This is both area efficient and power efficient.

Abstract: An amplifier, comprising: an amplifying element having an input side and an output side; a first transformer on the output side of the amplifying element arranged to mutually couple a fraction of the output current from the amplifying element onto the input side of the amplifying element; a second transformer on the input side of the amplifying element arranged to increase the input voltage on the input side via mutual coupling of its primary and secondary windings; wherein a primary winding of the first transformer is connected to an output of the amplifying element; wherein a secondary winding of the first transformer is ac connected to a secondary winding of the second transformer; and wherein the primary winding of the first transformer is dc blocked from the secondary winding of the second transformer. The negative and the positive reactive feedback loops are not formed from the same trifilar transformer.

Abstract: A circuit comprising: a passive reactive component; and an active circuit, the active circuit arranged to increase the ac voltage difference across the reactive component by changing the current at an input to the reactive component and the current at an output of the reactive component by equal and opposite amounts. By increasing the current on one side of the resonant circuit and decreasing the current on the other side of the resonant circuit, the amount of current flowing through the resonant circuit is increased and thus the ac voltage difference across the inductor of the LC resonant circuit is increased. The Q of an inductor (the ratio of its imaginary to real impedance) is increased. In a filter, the improved Q provides a sharp, high rejection notch and faster pass-band to stop-band roll-off, thus improving the frequency response of the circuit.

Abstract: A pulse generator comprising: a first signal generating arm comprising a first inductor and a plurality of switching elements, each arranged to draw current through the first inductor; and a controller arranged to activate the plurality of switching elements in a predetermined sequence so as to generate a predetermined pulse waveform at a pulse generator output. The switching elements of the signal generating arm and the inductor together form a pulse synthesizer that takes the signal from the controller and uses it to synthesize an output pulse. Compared with conventional transmitter architectures, the functions of the upconversion mixer, the DAC, and the power amplifier are all performed by a single simplified circuit. This is both area efficient and power efficient.

Abstract: An amplifier, comprising: an amplifying element having an input side and an output side; a first transformer on the output side of the amplifying element arranged to mutually couple a fraction of the output current from the amplifying element onto the input side of the amplifying element; a second transformer on the input side of the amplifying element arranged to increase the input voltage on the input side via mutual coupling of its primary and secondary windings; wherein a primary winding of the first transformer is connected to an output of the amplifying element; wherein a secondary winding of the first transformer is ac connected to a secondary winding of the second transformer; and wherein the primary winding of the first transformer is dc blocked from the secondary winding of the second transformer. The negative and the positive reactive feedback loops are not formed from the same trifilar transformer.

Abstract: A circuit comprising: a passive reactive component; and an active circuit, the active circuit arranged to increase the ac voltage difference across the reactive component by changing the current at an input to the reactive component and the current at an output of the reactive component by equal and opposite amounts. By increasing the current on one side of the resonant circuit and decreasing the current on the other side of the resonant circuit, the amount of current flowing through the resonant circuit is increased and thus the ac voltage difference across the inductor of the LC resonant circuit is increased. The Q of an inductor (the ratio of its imaginary to real impedance) is increased. In a filter, the improved Q provides a sharp, high rejection notch and faster pass-band to stop-band roll-off, thus improving the frequency response of the circuit.

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 continuous time counter and method of counting are provided, comprising a sequence of adding stages which build up the output based on the inputs by progressively adding new values to opposite ends of an output stack. The counter provides for fast and reliable continuous time counting operations.

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 continuous time counter and method of counting are provided, comprising a sequence of adding stages which build up the output based on the inputs by progressively adding new values to opposite ends of an output stack. The counter provides for fast and reliable continuous time counting operations.

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.