47 results about "Continuous wave interference" patented technology

The invention discloses an interference waveform self-adaptation offset method for continuous wave detection. The method comprises the first step of performing initializing; the second step of shielding a target echo signal; the third step of carrying out transmitting, receiving and primary offset; the fourth step of judging whether a detection period includes training time or not, wherein if yes, a detection target echo is shielded, and the fifth step is executed, and if not, the shielding on a detection target is cancelled, and the sixth step is executed; the fifth step of carrying out training, namely, a digital signal processing module trains an interference transfer function according to a sent signal and the echo signal and executes the third step; the sixth step of carrying out secondary offset. The invention further discloses an interference waveform self-adaptation offset device for continuous wave detection. The device comprises a transmitting module, a transmitting antenna, a receiving antenna, an interference offset module, a receiving processing module and the digital signal processing module. The method and device have the advantages of being high in electrical level self-adaptation, good in effect, convenient to achieve, capable of achieving the system easily, stable, reliable and the like.

The invention provides an open-loop detecting circuit for a frequency modulated continuous wave optical fiber gyroscope based on phase comparison, belonging to the technical field of an optical fiber gyroscope. The open-loop detecting circuit comprises an analogue pretreatment part and a digital domain treatment part, wherein the analogue pretreatment part comprises a band-pass filtering module, a shaping module, a multiplier, and an AD (Analogue / Digital) pretreatment part; the digital domain treatment part comprises an AD collector and an FPGA (Field Programmable Gate Array) programming module; and the AD pretreatment part comprises a low-pass filter and an AD head amplifier. The invention provides the open-loop detecting circuit for the frequency modulated continuous wave optical fiber gyroscope based on the phase comparison. The novel frequency modulated continuous wave interference type optical fiber gyroscope is quantitatively detected by detecting a phase difference of two paths of signals, so that the influence on phase difference detection, caused by frequency modulation period and amplitude variation, can be removed. The common-mode error of the optical fiber gyroscope can be restrained well in a differential detection manner.

The invention relates to the field of sanitary navigation and location and discloses a continuous wave interference signal estimator, an estimation method, a remover and a removing method. A digital phase-locked ring is adopted to detect the frequency or sine wave and amplitude of a continuous wave interference signal, a continuous wave interference estimation signal can be obtained easily, so that the continuous wave interference estimation signal can be removed conveniently. The digital phase-locked ring is a common circuit, FFT conversion and FFT reverse conversion are not required to be conducted on time domain signals received by a global navigation satellite system (GNSS) in real time, and complex technologies such as the FFT conversion and the FFT reverse conversion are avoided. The problem in the prior art that a continuous wave interference frequency point needs to be known in advance is solved. Further, a frequency band of a radio frequency front end output signal is divided into a plurality of sub frequency bands, the plurality of sub frequency bands can be processed respectively, hardware achieving difficulty is further reduced, and the processing speed is increased.