7results about "Modulation with suppressed carrier" patented technology

This invention discloses an amplitude-phase adjustable carrier generation device and method, belonging to the field of precision measurement and signal synthesis. The phase accumulator of this invention incorporates a phase adjuster. The phase adjuster counts the system clock, and when a set count value C is reached, it outputs a phase adjustment value S. At this time, the value of the phase register is simultaneously added to the frequency control word FCW and the phase adjustment value S. Subsequently, the phase register overflows, is cleared to zero, and accumulation restarts. The phase adjuster supplements the decimal part discarded during the rounding of the frequency control word FCW, which helps improve the frequency stability of the carrier. The CORDIC calculator of this invention employs a parallel interpolation structure, which can use n CORDIC cores to calculate the sine values ​​of n consecutive phases in parallel. The interval between two adjacent phases is the frequency control word FCW. The interpolation unit arranges the n data streams and outputs them serially. The parallel interpolation structure improves the speed and accuracy of CORDIC calculation through parallel computation, which can greatly reduce phase truncation errors and help reduce carrier spurious emissions.

A technique for generating electronic signals includes processing a respective first-level input signal by each of a plurality of first-level channels, including up-sampling the respective first-level input signal and single-sideband (SSB) modulating the up-sampled first-level input signal to produce a respective first-level output signal. The technique further includes processing a respective second-level input signal by each of a plurality of second-level channels, including up-sampling the respective second-level input signal and SSB-modulating the up-sampled second-level input signal to produce a respective second-level output signal. The plurality of second-level channels is arranged in multiple groups assigned to respective first-level channels, and the technique further includes (i) summing together the second-level output signals of the second-level channels in each group, (ii) providing a group sum as the first-level input signal to the first-level channel to which the group is assigned, and summing together the first-level output signals to provide a composite signal.

Method and device for converting an analog input signal into a digital output signal, wherein the analog input signal is supplied to be converted to the input side of an amplitude modulator with carrier suppression to obtain a carrierless amplitude-modulated signal, an adder adds a sinusoidal carrier signal offset by 90° to the amplitude-modulated signal output by the amplitude modulator to obtain a phase-modulated signal, the phase-modulated signal is supplied to a limiter that is used to suppress interference amplitude modulation in the phase-modulated signal, and the signal output by the limiter is supplied to a demodulator and sampled therein with at least one sampling clock signal, where the phase position of the at least one sampling clock signal is dynamically altered to achieve a higher resolution.

The invention relates to a synchronous modulation system using amplitude modulation, which basically consists of a modulator and a demodulator able to transmit digital signals at double the frequency of its carrier wave. For this purpose, the system uses analog and digital circuits that combine to modulate, separately, the positive half and the negative half of the carrier sine wave, such that in a single cycle of the carrier wave, two different information bits can be sent. The demodulator-modulator unit can be easily combined with other units to form wired or wireless communication systems and even optical or sonic systems with minimal generation of parasitic harmonics, resulting in a minimum bandwidth requirement for operation.

The invention presents methods for generating a feedback signal for an acousto-optical element (105) such that, despite amplification with a nonlinear transfer function, it exhibits the desired signal shape and that, during feedback control of an acousto-optical element (105), the nonlinearities of the amplifier (104) have no effect. The invention offers two methods based on pre-distorting the raw signal—before it is amplified to form the feedback signal—by comparing an amplified signal with the unamplified signal. One method uses the feedback signal itself, and the other uses a reference signal. (Figure 2)

An electromagnetic modulation device may include a receiver configured to receive electromagnetic signals, a digital-to-analog converter configured to continuously generate a modulation signal, a mixer coupled to the receiver and the digital-to-analog converter and configured to encode the electromagnetic signals received by the receiver with the modulation signal generated by the digital-to-analog converter upon receipt of the electromagnetic signals by the receiver, and a transmitter coupled to the mixer and configured to transmit the encoded electromagnetic signals generated by the mixer.