6 results about "Center frequency" patented technology

Disclosed is a method and an apparatus for channel estimation regarding electromagnetic wave multi-path characteristics between a sender and a receiver by using a chirp signal. The method includes the steps of (a) multiplying a received composite signal by a narrowband chirp-shift-keying signal or narrowband multiple center-frequency-chirp signal generated by the receiver itself and outputting a sum of individual frequency components resulting from difference in distance of multiple paths for up-chirp and down-chirp signal portions of a chirp-shift-keying signal, respectively, the received composite signal being formed by generating narrowband chirp-shift-keying signals or narrowband multiple center-frequency-chirp signals by the sender, sending the signals by a transmission antenna, receiving the signals by a reception antenna of the receiver via a multi-path channel, superimposing the signals, and adding the signals; (b) multiplying outputs of the up-chirp and down-chirp signal portions of the sum of individual frequency components and calculating a tolerance frequency output; (c) compensating for a frequency tolerance of the sum of individual frequency components by using the tolerance frequency output and generating a frequency compensation output; (d) compensating for discontinuity of chirp-shift-keying signals resulting from use of the narrowband chirp-shift-keying signals or the narrowband multiple center-frequency-chirp signals regarding the frequency compensation output and generating a discontinuity compensation output having no discontinuity; (e) decomposing the discontinuity compensation output into individual multi-path signals by using a frequency analysis method; and (f) extracting an attenuation component and a time delay component caused by the multi-path channel from the individual multi-path signals by using a size of frequency components of each frequency.

The invention discloses a relative motion speed tracking method and device, a readable storage medium and electronic equipment, and the method comprises the steps: carrying out correlation calculationon a received signal and a reference signal during each hopping in a current information bit, obtaining a single-hop complex correlation signal, and carrying out compensation calculation; performinginter-hop coherent accumulation calculation on each compensated single-hop complex correlation signal; calculating a phase value according to the real part and the imaginary part of the accumulated value, and unwrapping the phase value to obtain a processed target phase value; calculating a difference value between the target phase value corresponding to the current information bit and the targetphase value corresponding to the previous information bit to obtain a corresponding phase difference; and calculating the frequency difference corresponding to the phase difference, and calculating the relative motion speed deviation according to the frequency difference, the light speed and the average center frequency of the received signal. According to the method, a relative motion speed deviation calculation method different from the prior art is adopted, and tracking of the signal relative speed in frequency hopping communication can be completed with high precision.