Linearity vs. Power Consumption of CMOS LNAs in LTE Systems

Abstract

This paper presents a study of linearity in wideband CMOS low noise amplifiers (LNA) and its relationship to power consumption in context of Long Term Evolution (LTE) system. Using proposed figure of merit to compare 35 state-of-the-art LNA circuits published in recent years, the paper shows a proportional but relatively weak dependence between amplifier performance (that is combined linearity, noise figure and gain) with power consumption. As a result, the predicted increase of LNA performance, necessary to satisfy stringent linearity specifications of LTE standard, may require a significant increase in power, a critical budget planning aspect for both handheld devices and base stations operating in small cells.

Recent Developments in Integrated Interferer-Tolerant Receivers for Reconfigurable Radios

“…This TX leakage can modulate out-of-band interferers to the band of interest. A scenario for LTE Band 2 as discussed in [12] is shown in Fig. 3(b).…”

“…The OOB interferer in this depiction is a continuous-wave (CW) signal at 40 MHz offset with respect to the desired signal frequency ( f RX ). Notice that the duplexer only provides 4 dB filtering to the CW interferer due to the wideband LTE signal bandwidth [12]. For Band2 the TX signal is at an offset of 80 MHz [12].…”

“…Notice that the duplexer only provides 4 dB filtering to the CW interferer due to the wideband LTE signal bandwidth [12]. For Band2 the TX signal is at an offset of 80 MHz [12]. The TX leakage, therefore, produces in-band IM 3 products.…”

Estimation of a 10 Gb/s 5G Receiver's Performance and Power Evolution Towards 2030

“…There are a few LNA performance evolution studies available in literature and therefore it is selected as the RF Front End component in this work. In [6] the authors have examined about 30 papers published between 2004 and 2013, but only 2005 to 2011 contain more than one sample per year. Another previous work is the LNA roadmap [7] from 2001, which predicts a Figure-of-Merit (FoM) based on CMOS technology node evolution from 130 to 22 nm, but without details on power consumption.…”