To improve the level of protection of informative signal against impulse noise structural diagram of a synchronous detector with a controllable limitation (CL) was developed.
To increase the efficiency of noise reduction impact on the output of the synchronous detector (SD) that was implemented on 2 multiplier and low pass filter (LPF) 3, limiter 1 with adjustable limit level was set.
One technique uses a frequency-swept pilot tone and
synchronous detector to ascertain the average pilot tone power remaining within the final output.
As shown in Figure 2, Loop 1 employs an adaptive canceler.[4] In such a canceler, the amplitude and phase are adjusted automatically for cancellation of the strongest signal or signals present at the
synchronous detector. The
synchronous detector compares samples of the power amplifier input signal and the output signal taken, at error coupler C6.
The first cross-correlation establishes a baseline by correlating the reference signal at the synchronous detector with the reference signal through the signal controller and error path, which is the signal route from the sampler coupler to the synchronous detector by which the residual cancellation signal is measured.
In a closed loop operation, the digital integrator continuously reads error samples from the synchronous detector. The effect of noise and minimum achievable error level is continuously changing the calculated solution for cancellation.
The system measures the light transmission and backscatter from two
synchronous detectors. Formulaction introduced the Turbiscan earlier this year with a $100,000 price tag, and has already sold a few models.
The servo section has a microcontroller driven fundamental and second harmonic synchronous detectors, a servo integrator and a lock detector.
The servo board device generates reference signals to the switched capacitor filter and synchronous detectors, and handles lock acquisition and detection.
The vector voltmeter downconverts the signals twice, using local oscillators and mixers, to a low IF where the complex ratio of the two signals is found with
synchronous detectors. As the frequency of operation is increased into the mm-wave range, the coaxial transmission line, connectors and transitions between the analyzer and coplanar probe increasingly degrade the performance of the measurement system.