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RF Circuit Design - Coggle Diagram

- - - - Partion
      - Crystal and Transistor
      - Shot
      - Thermal
    - - Cosmic
      - Atmospheric
  - - - F (Noise Figure) = SNRin / SNRout
        
        SNRin = Si / Ni
        
        SNRout = Ap Si / Ap Ni + Na
  - - - Na = k Te Bn G
      - Ni = k Ts Bn
    - - Te = (F - 1) Ts
        
        T = T1 + (T2 / G1) + (T3 / G1 G2)
- - - - Stages
        
        Antenna
        
        RF Filter
        
        RF Amplifier
        
        Detector (Demodulator)
        
        Audio Amplifier
      - Circuit Diagram
      - Principle of operation
      - Disadvantages
      - Improving sensitivity
      - https://upload.wikimedia.org/wikipedia/commons/f/f9/Simple_TRF_receiver_block_diagram.svg
    - - Principle of operation
      - Circuit Diagram
      - Stages
        
        RF-LNA Amplifier
        
        Converter (Mixer)
        
        RF Filter
        
        Local Oscillator
        
        Antenna
        
        IF Amplifier
        
        Detector (Demodulator)
        
        Audio Amplifier
        
        AGC Circuit
      - Disadvantages
      - https://upload.wikimedia.org/wikipedia/commons/3/3f/Superheterodyne_receiver_block_diagram_2.svg
- - - - Always acts as an input
    - - Can be interchanged as output or 2nd input
    - - Can be interchanged as output or 2nd input
  - - - Wm = WRF
        
        Downconversion
        
        Difference frequency
        
        Reciever
      - Wm = WIF
        
        Upconversion
        
        Sum Frequency
        
        Transmitter
  - - - RF to lower IF
    - - Lower IF to RF
  - - - FLo < FRF
        
        Low-side injection
        
        Low-side downconverter
      - FLo > FRF
        
        High-side injection
        
        High-side downconverter
    - - Sinusoidal CW signal
      - Square Wave
  - - - Diodes
    - - Transistors
  - - - When to use?
        
        Overcome image rejection problem in case of small IF
      - Design RLC BPF
    - - How it works?
        
        Supresses one of the input sidebands by phase and amplitude cancellation
      - Advantage
        
        Can achieve 20dB of image rejection
      - When to use?
        
        Small IF
    - - Alternative names
        
        Bandpass preselection filter
        
        Image rejection preselector
      - Where?
        
        Between LNA and Mixer
      - Why?
        
        To supress the image signal (frequency)
      - Higher IF = Higher Image Rejection
      - LO & IF carefully selected
        
        To avoid image frequencies close to the desired RF
  - - - -10 log (Prf / Pif)
      - 4.5dB -> 9dB
    - - Amount of power leakage from one port to another
      - As Isolation increases, leakage decreases