Homodyne Receiver: Advantages and Disadvantages

This page covers the advantages and disadvantages of a Homodyne Receiver. It lists its benefits and drawbacks.

What is a Homodyne Receiver?

Introduction:

A Homodyne receiver doesn’t use an RF mixer to convert the modulated RF signal to baseband I/Q signals. The baseband signals are at zero frequency.

Figure 1: Homodyne Receiver architecture

The figure above depicts a typical Homodyne Receiver architecture.

A Homodyne receiver uses a Local Oscillator (LO) frequency that’s the same as the received signal frequency.

Figure 2: IQ demodulator

The figure above depicts an IQ demodulator. As shown, it converts the modulated RF signal into baseband I and Q signals. Here, W0 equals 2πF0 where F0 is equal to Fc (the Carrier Frequency) of the received modulated RF signal.

Benefits or Advantages of Homodyne Receiver

Following are the benefits or advantages of a Homodyne Receiver:

• It uses the same frequency for the LO as the transmitted RF frequency for conversion to zero baseband I/Q signal frequency. Hence, it has a very simple architecture.
• RF components such as LOs, RF mixers, and filters are not needed, unlike in a heterodyne receiver architecture. This means the cost of a homodyne receiver is less compared to a heterodyne receiver.

Drawbacks or Disadvantages of Homodyne Receiver

Following are the disadvantages of a Homodyne Receiver:

• Homodyne receivers suffer from LO (Local Oscillator) leakage. This leakage needs to be as low as possible in order to retrieve the baseband I/Q signals at zero frequency.