Input Analog Message Signal
The input chart now respects the true selected duration on the time axis. The drawing area is only shown when Draw with Mouse is selected. The drawing area also carries explicit axes.
Sampled Representation / Sampling View
Dense message waveform, sampling instants, and sampled points shown together. Sampling instants now use the real time step Ts = 1/Fs instead of an incorrect linspace spread.
Filtered / Prepared Baseband Signal
Signal after optional anti-alias conditioning and optional use of the sampled path. This is the baseband entering the modulation law.
Ideal Modulated Signal
Clean modulation result before practical channel impairment. AM shows carrier + sidebands; DSB-SC suppresses the carrier; SSB keeps only one sideband; FM/PM change angle rather than amplitude.
TX RF Signal
Practical transmit waveform. In this app it equals the ideal modulated signal before the channel, but is kept separately for product-family clarity and future extensibility.
RX Signal
Signal after channel effects: attenuation, fixed delay, optional echo, and AWGN. Architecture is ready for future fading, Doppler, CFO, phase noise, and nonlinear distortion.
Demodulated Signal
Raw recovered baseband after the chosen detector chain. Depending on modulation it is an envelope, a coherent product, an instantaneous-frequency estimate, or a phase-related quantity.
Reconstructed Output Signal
Overlay of the original message, the demodulated quantity, and the final reconstructed output after post-demod filtering and optional smoothing.
Dynamic Signal Chain Block Diagram
Clickable engineering signal-flow view. Blocks switch tabs or scroll to the relevant analysis card. Variables shown inside blocks are intrinsic to the block; side boxes hold supporting settings.
Message Spectrum
Spectrum of the original baseband message. Estimated message bandwidth is derived from this signal and used by the Nyquist analysis box.
Sampled-Signal Spectrum
Spectrum of the sampled signal representation. When Fs is not high enough relative to baseband bandwidth, spectral replication overlaps and aliasing becomes visible.
Modulated RF Spectrum
RF spectrum after modulation. AM shows carrier plus sidebands, DSB-SC removes the carrier, SSB keeps one sideband only, and FM/PM produce wider angle-modulated spectra.
Recovered Signal Spectrum
Spectrum after demodulation and reconstruction. Ideally it should match the baseband message spectrum within detector and filtering limits.
Nyquist / Shannon Analysis Box
Relationship between estimated message bandwidth, actual sampling frequency, and aliasing risk.
Detector Input
Signal entering the detector chain. For coherent methods this is the RX RF waveform; for envelope or discriminators it is the signal before the specific nonlinear or analytic operation.
Detector Internal Quantity
AM: envelope or rectified-smoothed quantity. DSB-SC / SSB: coherent product. FM: discriminator or instantaneous-frequency estimate. PM: phase-related detector quantity.
Output Baseband / LPF Output
Recovered message before final reconstruction finishing steps.
Original vs Recovered Comparison
Overlay of original message, raw demodulated signal, and reconstructed output to judge detector quality and filtering choices.
Error / Difference Plot
Original minus reconstructed output. Residual error reflects channel impairment, sampling limits, demodulation choice, and filtering quality.
Explanations
Technically correct guidance for the full analog signal path, sampling, spectra, modulation families, and detector interpretation.