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Superheterodyne Receiver Chain

Simulation of a basic superheterodyne receiver front-end combining multiple PathSim-RF blocks: an RF amplifier (LNA), a mixer for downconversion, and an IF amplifier. This demonstrates how the blocks compose into a complete signal chain.

Receiver Architecture

The receiver chain consists of:

LNA (Low Noise Amplifier): 15 dB gain, IIP3 = +5 dBm
Mixer: Downconverts RF to IF with 0 dB conversion gain
IF Amplifier: 20 dB gain, IIP3 = +15 dBm

The RF input at 1000 Hz is downconverted to an IF of 100 Hz using a 900 Hz LO.

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System Setup

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Connections

The signal flows: RF Source -> LNA -> Mixer (RF port) -> IF Amplifier -> Output. The LO connects to the mixer's LO port.

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10:58:24 - INFO - LOGGING (log: True)
10:58:24 - INFO - BLOCKS (total: 7, dynamic: 1, static: 6, eventful: 0)
10:58:24 - INFO - GRAPH (nodes: 7, edges: 8, alg. depth: 4, loop depth: 0, runtime: 0.093ms)
10:58:24 - INFO - STARTING -> TRANSIENT (Duration: 0.20s)
10:58:24 - INFO - --------------------   1% | 0.0s<1.5s | 1057.6 it/s
10:58:24 - INFO - ####----------------  20% | 0.3s<1.2s | 1077.8 it/s
10:58:24 - INFO - ########------------  40% | 0.7s<0.9s | 1068.6 it/s
10:58:25 - INFO - ############--------  60% | 1.0s<0.6s | 1091.9 it/s
10:58:25 - INFO - ################----  80% | 1.3s<0.2s | 1338.0 it/s
10:58:25 - INFO - #################### 100% | 1.5s<--:-- | 1443.6 it/s
10:58:25 - INFO - FINISHED -> TRANSIENT (total steps: 1614, successful: 1614, runtime: 1496.21 ms)

Signal at Each Stage

The scope shows the signal evolving through the receiver chain: the weak RF input, the amplified LNA output, and the downconverted IF output.

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Output Spectrum

The IF output spectrum shows the downconverted signal at MATHINLINE0ENDMATH Hz along with the image at MATHINLINE1ENDMATH Hz.

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