Bidirectional Bridge with Dual RMS Detectors Targets RF Power, Return-Loss Measurement (.PDF Download)

July 30, 2019
Bidirectional Bridge with Dual RMS Detectors Targets RF Power, Return-Loss Measurement (.PDF Download)

Directional couplers are used in a wide variety of applications to sense RF power, and they may appear at multiple points in a signal chain. In this article, we will explore Analog Devices’ ADL5920, which combines a broadband directional bridge-based coupler with two rms responding detectors in a 5- × 5-mm surface-mount package. This device helps overcome the struggle that conventional discrete directional couplers deal with regarding the tradeoff between size and bandwidth, particularly at frequencies below 1 GHz.

In-line RF power and return loss measurements are typically implemented using directional couplers and RF power detectors. In Figure 1, a bidirectional coupler is used in a radio or test-and-measurement application to monitor transmitted and reflected RF power. It’s also sometimes desirable to have RF power monitoring embedded in a circuit, with a good example being where two or more sources are being switched into the transmit path (either using an RF switch or with external cables).

Comments

To join the conversation, and become an exclusive member of Electronic Design, create an account today!