An adaptive multi-mode RF front-end for cellular terminals

Abstract

This paper presents a fully-integrated performanceon-demand receiver front-end for GSM/EDGE/W-CDMA/ CDMA2000 multi-mode cellular applications. The design's noise figure, linearity and selectivity are adapted depending on current environmental conditions and the selected standard to guarantee lowest overall power consumption. The single-chip zero-IF receiver comprises two self-matched LNAs for high/low-band, the demodulator and a fully-integrated ΔΣ−fractional−N PLL. The integration of I/Q-ADCs and a digital front-end (DFE) enables an efficient 3rd-order analog baseband filter. Accurate channel and matched filtering, sample-rate conversion and dynamic-range control are achieved in the DFE allowing for greater flexibility. In the absence of any blocker the performance of demodulator, VCO, analog baseband filter and DFE are adapted to reduce the current consumption up to 42 % versus the full-featured mode. The receiver has been fabricated in a 0.13 μm CMOS process and occupies 8 mm 2 die area. The design is verified by error-vector-magnitude (EVM) measurements exhibiting 3.9 % for W-CDMA and 3.1 % for CDMA2000.

A concurrent multiband CMOS low-noise amplifier for 4G standard receivers

“…Recently, there has been growing demand for multiple services within a single mobile terminal. For this purpose, multiband wireless receivers have been introduced . A multiband low‐noise amplifier (LNA) is one of the key building blocks in such receivers.…”

A concurrent triple‐band CMOS low noise amplifier for fourth generation applications

“…Recently, there has been growing demand for multiple services within a single mobile terminal. For this purpose, multiband wireless receivers have been introduced [3]. A multiband low noise amplifier (LNA) is one of the key building blocks in such receivers.…”

“…However, it is difficult to implement within the limited space available in mobile terminals due to the high isolation requirement between antenna elements. To improve the isolation between two antenna elements, various MIMO antenna approaches have been introduced to implement systems utilizing a ground with a slit and/or stub [2][3][4], a jointed radiator [5] or jointed shorting [6], and a resonator [7]. However, those methods cannot provide good isolation performance at frequency bands below 1 GHz.…”