%0 Journal Article %T A Low-Power Ultrawideband Low-Noise Amplifier in 0.18£¿¦Ìm CMOS Technology %A Jun-Da Chen %J Active and Passive Electronic Components %D 2013 %I Hindawi Publishing Corporation %R 10.1155/2013/953498 %X This paper presents an ultrawideband low-noise amplifier chip using TSMC 0.18£¿¦Ìm CMOS technology. We propose a UWB low noise amplifier (LNA) for low-voltage and low-power application. The present UWB LNA leads to a better performance in terms of isolation, chip size, and power consumption for low supply voltage. This UWB LNA is designed based on a current-reused topology, and a simplified RLC circuit is used to achieve the input broadband matching. Output impedance introduces the LC matching method to reduce power consumption. The measured results of the proposed LNA show an average power gain (S21) of 9£¿dB with the 3£¿dB band from 3 to 5.6£¿GHz. The input reflection coefficient (S11) less than £¿9£¿dB is from 3 to 11£¿GHz. The output reflection coefficient (S22) less than £¿8£¿dB is from 3 to 7.5£¿GHz. The noise figure 4.6¨C5.3£¿dB is from 3 to 5.6£¿GHz. Input third-order-intercept point (IIP3) of 2£¿dBm is at 5.3£¿GHz. The dc power consumption of this LNA is 9£¿mW under the supply of a 1£¿V supply voltage. The chip size of the CMOS UWB LNA is £¿mm2 in total. 1. Introduction The ultrawideband (UWB) system has become one of the major technologies for wireless communication systems and local area networks. The IEEE 802.15.3a ultrawideband (UWB) system uses a specific frequency band (3.1£¿GHz~10.6£¿GHz) to access data and employs the system of orthogonal frequency-division multiplexing (OFDM) modulation [1¨C3]. The frequency band consists of four groups: A, B, C, and D, with thirteen channels. Each channel bandwidth is 528£¿MHz, as shown in Figure 1. The system operates across a wide range of frequency 3.1¨C5£¿GHz or 3.1¨C10.6£¿GHz. The low frequency band from 3.1 to 5£¿GHz has been allocated for developing the first generation of UWB systems [4]. The system has several advantages such as low complexity, low cost, and a high data rate for the wireless system. In the front-end system design, a low-noise amplifier (LNA) is the first block in the receiver path of a communication system. The chief objective of the LNA is to reach the low-noise figure to improve the overall system noise [5]. The LNA must minimize the noise figure over the entire bandwidth, feature flat gain, good linearity, wideband input-output matching, and low power consumption. In the radio frequency circuit design, GaAs and bipolar transistors have performed fairly well. Nevertheless, these processes lead to increased cost and greater complexity. The RF front-end circuits using CMOS technology can provide a single-chip solution, which greatly reduces the cost [6]. With the rapid improvement of CMOS technology, it %U http://www.hindawi.com/journals/apec/2013/953498/