منابع مشابه
The NOMACand Rake Systems
• In the 1950s, Lincoln Laboratory developed the spread-spectrum Noise Modulation and Correlation (NOMAC) system for improved high-frequency radio communications. The production version of NOMAC, named the F9C, generated a pseudonoise (PN) sequence at the receiving terminal in synchronism with the PN modulation of the transmitted signal. The F9C achieved as much as 17 dB of jamming protection. ...
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Direct-sequence code-division multiple-access (DSCDMA) cellular systems, such as Wideband CDMA (WCDMA), are limited in performance by interference. Several types of Rake Receivers like A-Rake, S-Rake, P-Rake, Adaptive frequency Rake, Time frequency Rake, Conventional MMSE Rake and Adaptive MMSE rake are used for WCDMA. A Beam formerRake receiver can be an effective solution to provide the recei...
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A new method to deal with multi path fading environment for DS–CDMA wireless networks has been proposed. Here, depending upon the statistical nature of the channel, signal is transmitted as a sum of various spreaded signals; each one delayed and scaled according to the delay & strengths of the multi paths of the transmitted channel. New method known as Pre-Raking is performed at the transmitted...
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Adaptive space-frequency rake receivers use maximum ratio combining and multi-user interference suppression to obtain a considerable increase in performance in DS-CDMA systems such as WCDMA. To this end, the signal-plus-interference-and-noise and the interference-plus-noise space-time covariance matrices are estimated. The computational complexity is reduced significantly by transforming the co...
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This paper replicates Sims (2011) “stepping on a rake” model. It derives the model, shows how to solve it, offers some extensions, and boils the paper down to its central ingredient. Sims’ article is important: it is a simple modern economic model that produces a temporary decline in inflation when the central bank persistently raises interest rates. Inflation then rises. The model’s essential ...
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ژورنال
عنوان ژورنال: Acta medico-historica Rigensia
سال: 1997
ISSN: 1022-8012,2592-818X
DOI: 10.25143/amhr.1997.iii.41