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Kim J.,Marvell Semiconductor Inc. | Buckwalter J.F.,University of California at San Diego
IEEE Journal of Solid-State Circuits | Year: 2012

A fully-integrated Q-band (40-45 GHz) bidirectional transceiver is demonstrated in a 0.12-μm SiGe BiCMOS technology. The RF front-end design eliminates the need for transmit/receive switches by demonstrating a novel PA/LNA circuit. The transceiver has a transmit conversion gain of 35 dB with a 3-dB bandwidth of 4 GHz. The OP1dB is 8.5 dBm and Psat is 9.5 dBm. The transceiver has a receive conversion gain of 34 dB with a 3-dB bandwidth of 3 GHz. The noise figure is 4.7 dB and OP1dB is - 5 dBm at 43 GHz. The chip consumes 119.4 mW when transmitting and 54 mW when receiving, and overall chip size is 1.6 mm× 0.8 mm including pads. To the author's knowledge, this work represents the first switchless millimeter-wave bidirectional transceiver in a CMOS or BiCMOS process. © 2011 IEEE. Source

Kim J.,University of California at San Diego | Kim J.,Marvell Semiconductor Inc. | Buckwalter J.F.,University of California at San Diego
IEEE Journal of Solid-State Circuits | Year: 2012

A low-power, 40-Gb/s optical transceiver front-end is demonstrated in a 45-nm silicon-on-insulator (SOI) CMOS process. Both single-ended and differential optical modulators are demonstrated with floating-body transistors to reach output swings of more than 2 V PP and 4 V PP, respectively. A single-ended gain of 7.6 dB is measured over 33 GHz. The optical receiver consists of a transimpedance amplifier (TIA) and post-amplifier with 55 ω dB of transimpedance over 30 GHz. The group-delay variation is 3.9 ps over the 3-dB bandwidth and the average input-referred noise density is 20.5 pA/√Hz. The TIA consumes 9 mWfrom a 1-V supply for a transimpedance figure of merit of 1875ω/pJ. This represents the lowest power consumption for a transmitter and receiver operating at 40 Gb/s in a CMOS process. © 2012 IEEE. Source

Rong B.,Marvell Semiconductor Inc. | Ephremides A.,University of Maryland University College
IEEE Transactions on Information Theory | Year: 2012

We investigate the impact of a protocol-level cooperation idea in a wireless multiple-access system. By dynamically and opportunistically exploiting spatial diversity among the N source users, a packet is delivered to the common destination through either a direct link or through cooperative relaying by intermediate source nodes that have a statistically better channel to the destination. The traffic burstiness at the source is taken into account, and the performance metrics of the stable throughput region and delay are evaluated for the case of packet-erasure channels. We consider conflict-free, work-conserving transmission policies as well as plain time-division multiple-access policy. We establish that the stable throughput regions under both classes of cooperative policies are the same, which strictly contain the stable throughput regions achieved without cooperation. Moreover, the optimal policy for minimizing the average delay among the class of all cooperative work-conserving policies is determined. Then, in the case of two users, the closed-form delay expressions are explicitly derived as well. Our results indicate that cooperation can significantly reduce delay for both users. © 1963-2012 IEEE. Source

Oksman V.,Lantiq | Zhang J.,Marvell Semiconductor Inc.
IEEE Communications Magazine | Year: 2011

Narrowband power line communications (NB-PLC) systems operating in the frequency range 3-500 kHz were developed and used in the past few decades for telecommunications, metering, control, and automation. Recently, OFDM-based NB-PLC solutions known as G3 and PRIME came to the market after a long monopoly of single-carrier technologies, offering higher bit rates, robustness, and flexibility, which are vital for smart grid applications. However, it was realized that an international standard is important to ensure worldwide interoperable products and avoid market fragmentation. In the beginning of 2010, the IEEE Standards Association and ITU-T started standardization of NBPLC technologies based on OFDM, launching the P1901.2 and G.hnem projects, respectively. This article gives a technical overview of the ITU-T G.hnem standard, which defines a unified NB-PLC OFDM-based technology targeting multiple smart grid applications: smart metering, distributed automation, in-home energy management, generic home automation, car charging, and others, using IPv6 as the main networking protocol. ITU-T Recommendations G.9955 (G.hnem physical layer) and G.9956 (G.hnem data link layer) were consented for approval in February 2011; their final approval is expected in December 2011. © 2006 IEEE. Source

Zhang L.,Marvell Semiconductor Inc. | Wang H.,AT AndT Shannon Laboratories | Li T.,Michigan State University
IEEE Transactions on Wireless Communications | Year: 2013

This is Part I of a two-part paper that considers anti-jamming system design in wireless networks based on message-driven frequency hopping (MDFH), a highly efficient spread spectrum technique. In this paper, we first analyze the performance of MDFH under hostile jamming. It is observed that while MDFH is robust under strong jamming, it experiences considerable performance losses under disguised jamming from sources that mimic the true signal. To overcome this limitation, we propose an anti-jamming MDFH (AJ-MDFH) system. The main idea is to transmit a secure ID sequence along with the information stream. The ID sequence is generated through a cryptographic algorithm using the shared secret between the transmitter and the receiver, it is then exploited by the receiver for effective signal extraction. It is shown that AJ-MDFH can effectively reduce the performance degradation caused by disguised jamming, and is also robust under strong jamming. In addition, we extend AJ-MDFH to the multi-carrier case, which can increase the system efficiency and jamming resistance significantly through jamming randomization and frequency diversity, and can readily be used as a collision-free multiple access system. Part II of the paper focuses on the capacity analysis of MDFH and AJ-MDFH under disguised jamming. © 2013 IEEE. Source

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