Andreas Holm

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

This paper presents a fully-integrated performance-on-demand receiver front-end for GSM/EDGE/W-CDMA/CDMA2000 multi-mode cellular applications. The designpsilas 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 DeltaSigma.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 mum CMOS process and occupies 8 mm2 die area. The design is verified by error-vector-magnitude (EVM) measurements exhibiting 3.9% for W-CDMA and 3.1% for CDMA 2000.

A Single-Chip Dual-Band CDMA2000 Transceiver in 0.13μm CMOS

A single-chip dual-band transceiver for CDMA2000 is presented. For PCS, the zero-IF receiver achieves an NF of 9dB and an IIP3 of 0.5dBm at 32dB gain resulting in a maximal output SNR of 23dB. The key figures of merit for the transmitter are +13.5dBm maximum output power, ACPR1=-57dBc and ACPR2=-69dBc while drawing 34mA average current in typical environment.

Multi-Mode Receiver Design for Wireless Terminals

The ongoing evolution from 2G to 3G and beyond confronts the cellular market with the challenges of a broad diversity of communication standards. Furthermore, increasing levels of integration with minimum external component count, advances in semiconductor process technology, and the requirement for multi-mode operation are pivotal demands of the RF-IC manufactures to achieve fast design cycles and low product cost. As a result, reconfiguration of the wireless terminal has become the key issue in the design of wireless terminals. This paper discusses the requirements for multi-mode reconfigurable wireless receivers with focus put onto mixed-signal and digital enhancements to traditional analog front-end designs. The flexibility a digital-front-end (DFE) introduces is studied with respect to the main cellular communication standards (GSM/EDGE, CDMA2000, W-CDMA/HSDPA, and LTE) and satellite navigation systems (GPS, Galileo), with considerations of impacts on the capability of an implementation of a software-defined-radio (SDR).

A single-chip UMTS receiver with integrated digital frontend in 0.13 μm CMOS

A single-chip zero-IF UMTS receiver for the band classes I, II, and V is presented. The mixed-signal receiver comprises in the analog front-end two self-matched LNAs, an I/Q-mixer, and a fully-integrated DeltaSigma-fractional-N PLL with VCO. Hence, minimum external component count is achieved. The I/Q-ADCs and a digital front-end (DFE) located on the same die enables a shift of signal processing formerly performed in the analog front-end into preferred digital domain. The DFEs functionality mainly includes sample-rate conversion, channel filtering, dynamic range control and matched filtering. Through a high-speed digital serial interface the received and down-converted signal is finally further transmitted to the baseband IC. The presented RFIC, which is controlled via an integrated three-wire-bus interface, is realized in a 0.13 mum RF- CMOS process and occupies a die size of 8 mm . Measured key figures of merit show an NF of 7.8 dB at 48 dB gain of the analog part in band V and a maximum error-vector-magnitude (EVM) of 3.9%.

A single-chip dual-band CDMA2000 receiver for cellular terminals in 0.13 µm CMOS

Keeping pace with the steady advances in the development of even finer gate length technologies, CMOS has established as preferred process for radio-frequency design that enables the integration of complex digital circuitry on the same die at reasonable costs in terms of required area and power consumption. A single-chip dual-band CDMA2000 receiver based on zero-IF architecture is presented. In addition to all required analog building blocks for reception in the North-American cellular and PCS bands (Band Class 0 and 1), the chip features a fully integrated synthesizer including VCOs for minimum external component count, analog anti-aliasing filters, a fully configurable digital-front-end (DFE), DeltaSigma ADCs, a high-speed digital serial baseband (BB) interface, and a three-wire-bus configuration interface. The DFEs functionality includes sample- rate-conversion, channel filtering, dynamic range control, and signal conditioning for data transmission via a digital interface between RFIC and baseband IC. The receiver IC with a die size of 8 mm2 has been fabricated in 0.13-mum RF-CMOS and shows an error-vector-magnitude (EVM) of 3.1 % and a Rho of 0.998 at the digital baseband interface.

High-resolution optical probing of SAW and leaky SAW structures

A nondestructive high-resolution technique for the optical detection of surface acoustic wave (SAW) devices is presented. The laser probing technique allows for the measurement of the phase and amplitude of microacoustic fields and waves of SAW components in operation. The phase velocity can be determined directly from the measurements with a relative accuracy of up to 1.5.10/sup -5/. We present new experimental results of microacoustic wave propagation phenomena including anisotropic and temperature dependent phase velocity /spl upsi/, diffraction, and attenuation and compare them to full-wave analysis computations. The minimum detectable surface displacement of less than 1 pm//spl radic/Hz allows for the detection of different acoustic modes such as Rayleigh waves and leaky SAWs.

Laser probing system for the accurate detection of surface acoustic wave phase velocities

The present work demonstrates a high-resolution technique for the optical detection of the phase and amplitude of high frequency surface acoustic waves (SAWs). The test setup incorporates a mode-locked picosecond laser, harmonic mixing, and coherent detection, and it allows not only the measurement of the surface wave field but also the direct determination of the phase velocity. A measurement bandwidth in excess of 2 GHz is achieved. The maximum scan length was 4 cm. As a substrate, LiNbO3 has been used for the test measurements. Minimum detectable surface displacement and dynamic range were 1 pm/Hz1/2 and 40 dB, respectively. The method enables the determination of the phase velocity with a resolution of 1.5 (DOT) 10-5 in dependence of crystal cut, temperature, and frequency. An additional feature is that phase velocity values can be obtained with spatial resolution, i.e., velocity variation effects along the propagation path can be evaluated. We found that the assumption that the SAW velocity is constant across the whole device surface is not valid in general.

GPS/Galileo System-on-Chip with UMTS/GSM Support for Location Based Services Applications

A single chip receiver for GPS, Galileo, UMTS, CDMA2000 and GSM standards is presented for the first time. The analog Zero-IF front-end features 2 wideband paths for high and low band operation with one integrated wideband VCO. The paths are combined at the mixer and followed by a baseband filter, high resolution I/Q Σ-Δ ADC (83dB SNR for GPS/Galileo standard) and reconfigurable digital front-end for additional signal filtering and conditioning. For GPS/Galileo standards, the chip features overall NF of 3.2 dB (with external components) and gain of 110dB in the analog and digital part. The measured in-band IIP3 and IIP2 equal -25dBm and 20dBm, respectively. The chip is supplied from 1.5V and 2.85V voltage and consumes 66mA of current. The receiver is fabricated in 0.13um RF-CMOS technology and housed in a WFBGA-81 package. Index Terms—CDMA2000, Galileo, GPS, GSM, Location Based Services, multi-standard receiver, System-on-Chip, UMTS. I. INTRODUCTION Analysis of the current handset market reveals the grow- ing role of connectivity features in mobile terminals. Apart from calling and text-messaging functions, data transfer and localization are the most important services offered by net- work providers. Therefore, reliable and cheap RF front-end design is necessary to satisfy the requirements of equipment manufacturers and users, especially for entry phones and emerging markets. The CMOS technology offers potential for miniaturization, low price and reduced power consumption. On the other hand, challenges of multisystem integration, coexistence of analog and digital blocks and system perfor- mance arise. This paper presents a novel approach to multi- standard receiver design. A powerful solution is presented based on wideband analog design and reconfigurable digital approach. The coexistence of mobile and navigation systems were considered during the concept phase of the development and resulted in an architecture presented in Fig. 1. In order to fulfill the cost requirements and flexibility of implementation, two Zero-IF fully differential paths were designed, which can be adapted for the required standard using the selection of off-chip components. For Location Based Services Solution, one of the paths enables reception of navigation signals, while the other supports reception of assistance data from UMTS or GSM system (1). The integrated low noise amplifiers (LNA) and mixers are wideband and are designed for optimization of chip size and linearity. The

RF front-end system design for location based services applications

This paper presents feasibility studies for the implementation of a multi-standard, multimode RF front-end enabling utilization of Location Based Services (LBS) in a mobile handset using A-GPS system with GSM and UMTS support. A short description of the proposed system architecture is presented. The setup is proven based on the system simulations using Matlab. The influence of gain compression, wideband noise and reciprocal mixing on the system performance due to a full-duplex interferer is described. The analysis is extended for intermodulation test cases in a mobile environment. Feasibility analysis is confirmed with measurements of a GPS/Galileo/UMTS/CDMA2000/GSM reconfigurable front-end implemented in 130nm CMOS technology.