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ABSTRACT: The 32 nm implementation of an AMD x86-64 core occupying 9.69 mm<sup>2</sup> and containing more than 35 million transistors (excluding L2 cache), operates at frequencies >3 GHz. The core incorporates numerous design and power improvements to enable an operating range of 2.5 to 25 W and a zero-power gated state that make the core well-suited to a broad range of mobile and desktop products.
Solid-State Circuits Conference Digest of Technical Papers (ISSCC), 2010 IEEE International; 03/2010
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ABSTRACT: We consider a population of HIV infected patients. In resource poor environments, decision makers must allocate antiretro-viral drugs (ARVs) to patients in need of them the most. Further complicating matters is that once a patient is given ARVs, the decision maker must decide when to deny further access to ARVs. We compare various methods for determining which patients should receive ARVs and when to switch a patient off of ARVs. We examine the World Health Organization's (WHO) treatment recommendations and how the level of drug shortages can influence the performance of these recommendations. Instead of a single recommendation, the WHO offers three distinct treatment policies with no mention of when to use them. We find that the severity of drug shortages can greatly impact the performance of these policies and the performance gap can be as high as 1.4 years.
Simulation Conference (WSC), Proceedings of the 2009 Winter; 01/2010
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ABSTRACT: Future military communications systems, on both national and international levels, will demand the capability of transmitting high data rates over self-organising ad-hoc networks. In the work presented in this paper we describe a high data rate signal in space (HDR-SiS) developed by Rohde & Schwarz, that enables the transmission of real time video, voice and data in a mobile ad-hoc network (MANET). The transmission scheme uses OFDM at bandwidths ranging from 1 MHz to 10 MHz in order to be adaptable to various national and international spectral usage requirements. OFDM has the advantage of a high spectral efficiency and, given an appropriate design, simple equalisation techniques can be used in order to deal with multi-path channel environments. Although OFDM is already used in many standards such as WLAN, WiMAX, DVB-T, these systems were designed for either stationary and/or indoor applications. The presented SiS is optimised for mobile operators with relative speeds up to several hundred kilometres per hour and multi-path delays corresponding to relative distances of around 15 km
Military Communications Conference, 2006. MILCOM 2006. IEEE; 11/2006
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ABSTRACT: For joint source channel coding we extend the concept of incremental redundancy to a combination of decremental and incremental redundancy in a parallel concatenated turbo scheme. Even for compression only the new scheme outperforms Lempel-Ziv compression, but has many advantages in adaptive type II FEC/ARQ systems for the transmission over noisy channels.
Control, Communications and Signal Processing, 2004. First International Symposium on; 02/2004
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ABSTRACT: The ever increasing speed of data transmission, especially in
optical channels, in magnetic recording devices and in wireless links,
makes it necessary to look at new receiver structures which are capable
of high speed processing at low power consumption. Analog, nonlinear and
highly parallel operating circuits can perform the tasks of
equalization, differential detection, channel decoding and, in some
cases, of source decoding which are normally assigned to digital
processors and circuits. The first prototype analog VLSI chips of simple
decoder components are available and perform well at speeds up to 10
Gbit/s
Broadband Communications, 2002. Access, Transmission, Networking. 2002 International Zurich Seminar on; 02/2002
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ABSTRACT: A novel analog decoder design for high rate convolutional codes is
presented. The decoder complexity is considerably reduced compared to
conventional approaches in analog VLSI
Information Theory, 2001. Proceedings. 2001 IEEE International Symposium on; 02/2001
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ABSTRACT: Recently, several VLSI implementations of analog decoders have
been reported for rate 1/2 tailbiting convolutional codes. The main
advantages of analog decoders are much higher decoding speed, smaller
chip size and lower power consumption when compared to an equivalent
digital decoder. Since many high speed applications require code rates
well above 1/2 we focus on high rate tailbiting convolutional codes. For
digital decoder implementations it has been shown by C. Weiss and J.
Berkmann (see Proc. 3rd ITG Conf. Source and Channel Coding, Munich,
Germany, p.199-207, Jan. 2000) that it is advantageous to use the
trellis of the dual code which is less complex for high rate codes. The
novel analog decoder design proposed in this paper can be seen as a
direct analog implementation of the algorithm described by Weiss and
Berkman
Information Theory Workshop, 2001. Proceedings. 2001 IEEE; 02/2001
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ABSTRACT: The turbo-principle is more far reaching than the original turbo
code concept. Encoded DPSK transmission, e.g., can be viewed as a serial
concatenation of a channel code with a rate-one code representing the
DPSK modulation. Iterative decoding of this concatenated scheme shows
surprisingly good performance. We describe the serial concatenation of
interleaved tail-biting convolutional codes (TBCC) with this DPSK
rate-one code transmitted over AWGN and flat Rayleigh fading channels.
The receiver performs time-continuous “turbo” iterations
between the inner and outer codes and is realized by two analog ring
networks connected via an interleaver ring which exchanges extrinsic
information by means of analog signals being continuous in time and
value
Information Theory, 2000. Proceedings. IEEE International Symposium on; 02/2000
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ABSTRACT: We present an analog rotating ring decoder for decoding an LDPC convolutional code. The decoder architecture uses a window of soft received L-values, K time units in the past and K time units in the future, to decode a given bit. The window of 2K+1 time units is arranged in a ring structure, and decoding proceeds in a continuous fashion by rotating around the ring. Simulation results indicate performance almost identical to that achieved with digital decoding.
Information Theory Workshop, 2003. Proceedings. 2003 IEEE;
