Apparatus and method for receiver with interference tolerance

摘要

A receiver apparatus adapted to be synchronized with a link transmitter to identify and isolate a transmitted, modulated carrier signal from other RF transmissions by obtaining A/D samples at each integer π zero crossing of a transmitted signal and at the half Hertz cycles (π/2 and 3 π/2) of the modulated carrier signal. The integer π A/D samples are at the carrier signal zero crossings and thus contain only the other RF and noise in the receiving antenna. The half Hertz cycle A/D samples contain both the carrier signal and the other RF being received at that instant. The analytical methods of the invention use the integer π A/D samples to compute estimates of the other RF in the half integer π A/D samples in order to separate it for the detection of the transmitted signal, thereby benefiting narrow band signals with constant zero crossing that are directly coded on the carrier frequency as DC balanced symbols, and enabling higher data rates than are typically achievable by passband filtering the receiving antenna waveform.

主权项

1. A method of continuously monitoring wireless data transmissions, comprising:
a. generating a clock signal; b. receiving a radio frequency (RF) carrier signal having a waveform with an antenna operatively connected to a receiver, the carrier signal having an amplitude s, a frequency f which defines continuous hertz (Hz) cycles, and being generated by a communications channel or link transmitter, the carrier signal being modulated and adapted to transmit information and/or data in the form of a data stream or data block continuously in hertz cycles of frequency f, and other RF energy transmissions generated by other transmitters and emitters (other RF), the other RF energy transmissions having an amplitude r; c. amplifying the carrier signal and the other RF; d. sampling the antenna waveform atπ2in a hertz cycle containing the sum of the carrier signal and the other RF as defined by an equation a0.5=s0.5+r0.5 and sampling the antenna waveform at 3π2in a hertz cycle containing the sum of the carrier signal and the other RF as defined by an equation a1.5=s1.5+r1.5;
e. estimating a zero crossing time z01 between 0π and 1π of the other RF defined by an equation z01=r0/(r0−r1); f. estimating a zero crossing time z12 between 1π and 2π of the other RF as defined by an equation z12=1+r1/(r1−r2); g. estimating the amplitude and sign of the other RF in aπ2A/D sample in a hertz cycle using a linear curve fit interpolation given by an equation r0.5=(r0+r1)/2;
h. estimating the amplitude and sign of the other RF in a 3π2A/D sample in a hertz cycle using a linear curve fit interpolation as defined by an equation r1.5=(r1+r2)/2;
i. estimating the amplitude and sign of the other RF in a 3π2A/D sample in a hertz cycle using a linear curve fit extrapolation defined by an equation r1.5=2r1−r0.5;
j. estimating the amplitude and sign of the other RF in aπ2A/D sample in a hertz cycle using a linear curve fit extrapolation, the other RF amplitude and sign being defined by an equation r0.5=2r1−r1.5;
k. estimating the amplitude and sign of the other RF in aπ2A/D sample in a hertz cycle using a linear curve fit extrapolation given by an equation r0.5=2r0−r1.5, wherein r1.5 is from an immediate prior time hertz cycle;
l. estimating the amplitude and sign of the other RF in a 3π2A/D sample in a hertz cycle using a linear curve fit extrapolation given by an equation r1.5=2r2−r0.5, wherein r0.5 is from an immediate next time hertz cycle;
m. estimating the amplitude and sign of the other RF in aπ2A/D sample in a second direction in a present time hertz cycle using a quadratic curve fit interpolation, the other RF amplitude and sign being defined by an equation r0.5=−r1.5/3−r1+r0/3;
n. estimating the amplitude and sign of the other RF in a 3π2A/D sample in a hertz cycle using a quadratic curve fit interpolation, the other RF amplitude and sign being defined by an equation r1.5=−r0.5/3+r1+r2/3;
o. estimating the amplitude and sign of the other RF in aπ2A/D sample in a hertz cycle using a quadratic curve fit interpolation, the other RF amplitude and sign being defined by an equation r0.5=−r1.5/3+r0+r1/3, where r1.5 is from the immediate prior time hertz cycle;
p. estimating the amplitude and sign of the other RF in a 3π2A/D sample in a hertz cycle using a quadratic curve fit interpolation, the other RF amplitude and sign being defined by an equation r1.5=−r0.5/3+r2+r1/3 where r0.5 is from the immediate next hertz cycle;
q. separating the other RF from the carrier signal to enhance detection of the carrier signal; r. synchronizing the receiver and the link transmitter; and s. outputting the data to a user.