Link-budget calculations for CMOS integrated microwave receivers

Abstract

In this paper, advanced link-budget calculations for microwave receivers are introduced. Microwave receivers typically consist of narrowband circuits in the high frequency part and broadband circuits in the baseband part. In general narrowband circuits and broadband circuits are characterized in different ways. Narrowband circuits are described by impedance matching, power gain and noise figure while broadband circuits by voltage gain and input referred noise. This makes the link-budget calculation not straight-forward and often leads to errors. The paper presents a way to calculate link-budgets from the received power at an antenna output until an analog-to-digital converter's output. This incorporates narrowband and broadband circuits. At first a formel-set from theory is derived and furthermore applied to two practical case studies. The first case study is a 24 GHz CMOS receiver intended for industry radar while the second case study is a full W-Band CMOS receiver intended for 100Gb/s communication.