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223 Threads found on Phase Modulation
I need to make an amplifier which could amplify very small signals (uV) embedded in noise. The frequency of the signal to be amplified is known. The problem is that the signal has too much noise around it. I was told that a lock-in amplifier or phase sensitive detection (demodulation) can solve the problem but i don't know how to make it. Please he
AC, PWM?? Are you really using PWM or is it actually phase control? People in this forum often confuse both terms all the time. Use RMS current values.
phase-shift keying (PSK) is a digital modulation scheme that conveys data by changing (modulating) the phase of a reference signal (the carrier wave). The modulation is impressed by varying the sine and cosine inputs at a precise time. It is widely used for wireless LANs, RFID and Bluetooth communication. Best Essay W
How to draw the Phasor diagrams of A.M and F.M. what are the reasons for the following two cases (1). In A.M the resultant of the two side band vectors is always in-phase with carrier component ,Why? (2). In F.M the resultant side band vector is always in phase-quadrature with carrier component,Why?
Hello, i am trying to simulate Three phase inverter with first order sigma-delta modulation in matlab/simulink. Here is my simulink file. 135998 When you look at simulation results, phase currents looks pretty fine but phase-to-phase and phase-to-ground voltages looks like there are (...)
If I am not incorrect the posts #3 and #1 are independent. If this is so, then you should be creating a new thread. Do you have any vhdl program which will enable us to physically see sine wave with phase shifts,shifting according to the changing value of the input signal. Question is do you want the sine wave gen module to be
Hi I have found two types of BIDIRECTIONAL audio I/Q (45 degrees difference) phase shift networks, which I have enclosed in red squares. I wonder, which of the two is better, in the sense that keeps the phase difference more constant throughout the 300Hz-3KHz audio region? A third method is the polyhase network obrazki.elektro
I have designed a phase modulator(analog) at 4GHz using hyper abrupt varactor diodes. Technique used is reflective type,using quadrature hybrids. I have chosen hyper abrupt diodes(GaAs,gamma>1) to get higher sensitivity(radians/V).Though, I achieved ) 0.7 rad/Vpp sensitivity but at the expense of higher distortion,more than 5% and higher AM%.
determine the instantaneous frequency in hertz, the bandwidth and frequency deviation of the signal: f(t)= cos (200*pi*t) cos (5 sin (2*pi*t))+ 2 sin(100*pi*t) sin(5 sin 2*pi*t) cos (100*pi*t)
x(t)= 10 cos . what is the max phase and frequency deviation
In principle, indirect FM modulation of a generator signal can be achieved via phase modulation. But because the message signal has to be integrated before being passed to the phase modulator, the required phase shift for low frequency message components would be unfeasibly high. With modern signal (...)
What is the fourier transform of signals that are transmitted using QAM technique ? for any example, i only need to know how they occupy the same band with 90ْ phase shift?
Objective: is designing a synchronizer (connect a micro hydro plant with the grid) and I want to know when these two signals are in phase to close the breaker. Plan: was to get the difference between the signals and when it reaches 0 (as close as possible), it means that the signals are in phase. Resulting waveform of the difference is like th
In all the direct-conversion architectures I am facing there is the presence of I and Q carriers. Razavi in his book RF Microelectronics states that for zero IF receivers, the BB signal may have a chance of self-corruption. So, in order to alleviate this problem the signal is downconverted to in-phase and quadrature-phase and the signal will not b
The problem I have is that with PIC I generates only 3PWM while I need six,is it possible with IR2110 to input the same signal on LIN and HIN so that I obtained conveniable signals at pin1 and pin 7 for half bridge driving??? Thank you If you give the same signal to the LIN and HIN terminals of the same IC, then you
Hi, That will be done using phase variation check.
Hi, I need to generate a more complicated clocking waveform. For the proof of concept I think about "brute-forcing" it with an RFDAC. Unfortunately I can not find any information of expected performance in terms of phase noise/jitter of a clock that is generated with an RFDAC. The datasheets do not contain these plots. Does anyone have exp
more commonly today Symbol Rate= Baud Rate is only same as bit rate using 1 bit per symbol. Compression methods include N level amplitude and phase point to represent many bits into one symbol to maximize bandwidth compression in Bit's per Hertz. Other variables are redundancy, FEC, tolerance to fading, modulation type, group delay, multi-channe
Hello, I was working on some rectifier circuits and I saw this circuit on a board. It is a part of a complex power supply circuit. As my experiments, it works very well and can generate 380V mean voltage (per capacitor) on capacitors. The IGBTs use 15kHz gate signal, and duty cycle is various because of the feedback. However I did not see any si
Hey, I want to do a phase modulation for an high frequency signal using ADS. There is several phase modulator in ADS like: PM_ModTuned and PM_Mod (Time Modem). I have simulated in Envelope and Harmonic Balance, but in these 2 cases i don't get my input signal modulated. Any Suggestions?? Thanks. Zeina