%0 Journal Article
%T High-Gain Power-Efficient Front- and Back-End Designs for a 90£¿nm Transmit-Reference Receiver
%A Apratim Roy
%J ISRN Electronics
%D 2012
%R 10.5402/2012/435209
%X A new microwave receiver configuration which transmits reference pulses embedded in data streams for synchronization is analyzed with a 90-nm IBM CMOS standard. A two-stage cascode low-noise amplifier (LNA) is proposed for the receiver front-end which is matched by a passive network to save on power-expensive matching techniques. The amplifier exploits a double-differential topology and achieves a below 4£¿dB noise figure near the center frequency. The overall 3-dB bandwidth is 3.3£¿GHz with peaking up to 20.5£¿dB in the -band. The back-end of the receiver is implemented through an adjustable analog window-detection circuit. It avoids the use of control voltage generators and sample-hold (S/H) blocks to save electronic overhead and is simulated with a 0.1~2.0£¿Gbps pulse stream. The achieved speed-to-power ratio for the back-end has a maximum limit of 266£¿GHz/W. When compared against simulated results of published literature, the proposed designs show improved performance in terms of small-signal gain, noise, speed, and power dissipation. 1. Introduction The ultrawideband technology, with benefits like high data rate, low cost, and low complexity, has been considered as a promising initiative for short-distance wireless applications [1]. The main challenge of designing a wideband transceiver involves satisfying linearity, reverse isolation, gain, and noise requirements over a wide bandwidth. Different circuit techniques have been proposed in recent literature to achieve wideband operation for a radio-frequency (RF) front-end [2, 3]. Focus on the design of the back-end section of the receiver, on the other hand, has received relatively less attention. The wide variety of modulation and multiplexing techniques employed by the ultrawideband (UWB) system allow it to achieve high bit rates over a wide frequency range. For example, recent developments in UWB standards have proposed to exploit OFDM (orthogonal frequency division multiplexing), IR (impulse radio), and TR (transmit-reference) modulation techniques. Among them, IR-UWB is suitable for low rate applications (e.g., sensor network) and OFDM-UWB is more appropriate for high data rate transmission [4]. The idea of a transmit-reference (TR) system is that by injecting a reference pulse over the same channel as the information signal estimation of the channel model (to be directly used for convolution by a mixer) can be avoided. It is recognized that a TR system may face some limitations for a band-limited channel, but it allows data symbols to be decoded without direct calculation of multipath channel
%U http://www.hindawi.com/journals/isrn.electronics/2012/435209/