RF Duplexer and Diplexer: Selection Guide, Benefits & Manufacturers

Introduction

RF duplexers and diplexers are crucial components in RF systems, enabling simultaneous transmission and reception. Choosing the right one requires careful consideration of frequency bands, isolation, and insertion loss.

What is an RF Duplexer?

An RF duplexer is a three-port RF device used to separate frequency bands that are close to each other in wireless systems. For example, a GSM duplexer separates the uplink (890 to 915 MHz) and downlink (935 to 960 MHz) frequency bands. This is illustrated in Figure 1.

RF duplexers can be constructed using RF circulators or PIN diode switches. They are primarily used to share a single antenna between the transmitter and receiver sections of a transceiver.

Figure 1: RF Duplexer

What is an RF Diplexer?

An RF diplexer is also a three-port RF device, but it’s used to separate frequency bands that are farther apart in a wireless system.

Selection Guide

When selecting an RF duplexer or diplexer, consider the following parameters:

• Frequency Bands: The specific frequencies the device needs to handle.
• Higher Isolation between ports: Minimizing signal leakage between ports.
• Lower Insertion Loss: Reducing signal attenuation as it passes through the device.
• Power Handling Capability: The maximum power the device can handle without damage.
• Impedance Matching: Ensuring compatibility with the system (typically 50 or 75 Ohm).
• Filter Type: The type of filter used in the design (e.g., cavity, ceramic, or SAW filters).
• Port Configuration: The arrangement of input and output ports.
• Size & Form Factor: The physical dimensions and shape of the device.
• Operating Environment: The conditions in which the device will operate (temperature, humidity, etc.).

Advantages of RF Duplexers and Diplexers

Here are some of the benefits of using RF duplexers and diplexers:

1. Simultaneous Transmission and Reception: Enables simultaneous transmission and reception on different frequencies using a single antenna.

2. High Isolation: Offers high isolation, which minimizes signal leakage between Transmit (Tx) and Receive (Rx) ports, thus improving overall system performance.

3. Space Saving: Eliminates the need for separate antennas, saving valuable space in wireless communication systems.

4. Optimized Filtering: Uses optimized filtering to reduce noise and unwanted signals, ensuring cleaner communication.

5. Broad Application Range: Supports a wide range of applications, including cellular networks, satellite communications, radar, and Wi-Fi systems.

RF Duplexer Manufacturers | RF Diplexer Manufacturers

The following table lists popular manufacturers and vendors of RF duplexers and RF diplexers:

Conclusion

Selecting a high-performance RF duplexer or diplexer can significantly improve signal efficiency in wireless communication systems. Explore trusted manufacturers to find the best solutions for your specific needs.