Accurate Isolation Networks in Quadrature Couplers and Power Dividers | IEEE Journals & Magazine | IEEE Xplore

Accurate Isolation Networks in Quadrature Couplers and Power Dividers


Abstract:

When quadrature couplers and power dividers are implemented in integrated circuits, accurate isolation networks can not be realized due to the nonideal resistors and the ...Show More

Abstract:

When quadrature couplers and power dividers are implemented in integrated circuits, accurate isolation networks can not be realized due to the nonideal resistors and the process variations. We present an isolation network design technique which cancels the resistor parasitic effects and also increases the tolerance to variations in the resistance values. A Lange coupler and a power divider are designed at Ka-band using the proposed accurate and process-tolerant isolation networks. The improvement is analytically shown and empirically verified with our in-house GaN-based microstrip MMIC process. For the coupler, the measured return losses and isolation are better than 20 dB from DC to 40 GHz. The power divider achieves 20 dB return losses and isolation in a fractional bandwidth of 50%. Both devices maintain 20 dB performance even when the variation in sheet resistance is as high as 30%.
Page(s): 1148 - 1152
Date of Publication: 03 November 2020

ISSN Information:


I. Introduction

Quadrature couplers and power dividers are widely used for splitting and combining RF power at the input and output of balanced amplifiers [1]. Such configurations require the isolation ports of the quadrature couplers to be terminated with 50 resistors. Also, power dividers use resistors in their isolation networks.

References

References is not available for this document.