Patent ID: 9134355
Filing Date: 2015-09-15
Classification: G01R

Abstract:
1. A Broadband Receiver usable as an Adaptive Sweep Spectrum or Signal Analyzer (BASA) capable of accurate scanning and measurement of unknown signals at very high speeds and with very high levels of accuracy, consisting of: a Signal Splitter at the input to the BASA to split an incoming signal into two parts; two Local Oscillators whose output frequencies are symmetrically apart at a selectable frequency separation from the frequency of the incoming signal being scanned for, the Local Oscillators being tuned together through a frequency range of interest for the measurement; two Mixers, each of whose input Radio Frequency (RF) signals is one of the two outputs of the Signal Splitter, and each of whose Local Oscillator is one of the two Local Oscillators that are tuned together; two Low Pass Filters whose bandwidth can be made arbitrarily small to increase accuracy or arbitrarily large to increase speed of scanning and signal identification, respectively filtering the outputs of the two mixers to output any mixer product signals or noise within the low pass filter bandwidth; two Detectors one each at each low pass filter output that detects and outputs a DC voltage proportional to the input power into each Detector; an Analog Multiplier that multiplies the two low pass filtered and detected mixer outputs; a Video Filter and Logarithmic or Linear Amplifier combination whose input attaches to the Analog Multiplier's output and whose output is connected to a display or to a signal processor or analyzer; wherein when the BASA is used as a Spectrum Analyzer, the X-axis of the Spectrum Analyzer display is a voltage proportional to the incoming frequency being scanned for as a fraction of the total frequency range being scanned for signals, and the Y-axis of the display is the detected and amplified output of the Analog Multiplier; wherein if there exists a signal, or if there exists noise at the frequency being scanned at the input to the BASA, the detected and amplified output of the Analog Multiplier is proportional to the power of the incoming signal or noise power within the Low Pass Filter bandwidth; wherein the need for preselection filters at the input so as not to have spurious images is eliminated by a dual Mixer, Local Oscillator, and Low Pass Filter combination, allowing much higher speeds of spectrum scanning and digital phase locked loop accuracy at every frequency wherein the amplitude accuracy can be controlled via programmable attenuators or some closed loop method that corrects any input splitter imbalance if needed as a function of incoming frequency being scanned for.