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Independent component analysis (ICA) is a technique which is used to separate mixed signals. This paper presents an ICA implementation on FPGA utilizing negentropy maximization criteria for updating un-mixing weighting vector. We use this method to separate 4-channel comparatively fast mixed communication signals at the receiver. And before ICA processing, the mixed signals are often required whitening...
This paper presents realization of positioning based on DTMB (Digital Television Terrestrial Multimedia Broadcasting) and GPS (Global Positioning System) in urban or indoor environment by means of a Software Defined Radio (SDR). DTMB signal's unique feature in super-frame is analyzed and a new correlation method without generating local PN sequence is proposed. Double delta correlator and Kalman filter...
This paper presents a multi-bit discrete time sigma-delta converter for orthogonal frequency division multiplexing ultra wide band systems adopted by IEEE 802.15.3a and ECMA368 standard. An intact scheme of timing synchronization algorithm is also proposed for the receiver. The overall sigma-delta converter consists of two modulators. The low and high subbands of signal are operated by using third-order...
A multi-bit discrete time sigma-delta converter for an orthogonal frequency division multiplexing ultrawideband system has been designed. The overall sigma-delta converter consists of two modulators. The low and high subbands of signal are operated by using third-order low pass and fourth-order band pass modulator respectively. A simulation has been designed to realize the system with the converter...
Based on the high peak to average power ratio of orthogonal frequency division multiplexing systems, several methods of reducing the peak to average power ratio were analyzed. Then a method based on Golay complementary sequences was proposed to realize the low peak to average power ratio. The high peak to average power ratio sequences were encoded into Golay complementary sequences, peak to average...
The mathematical rhythm is a worldwide artistic language. In this study, many Mathematical rhythms existing in traditional Chinese art are analysed, including lines, proportion, symmetry, infinity, cycle and numbers. The integration of classical Chinese art and mathematical rhythms makes the art presents a unique beauty-the mathematical aesthetic, which reveals the rational and scientific thinking...
A novel carrier frequency offset tracking scheme for multilevel quadrature amplitude modulation-orthogonal frequency division multiplexing (MQAM-OFDM) systems is proposed using a designed conjugate code composed of MQAM mapping values and their complex conjugates which can also reduce peak-to-average power ratio (PAPR). The peak power is reduced by phase cancellation in the conjugate pairs avoiding...
In this paper, we investigate secret communications over a two-user semi-deterministic broadcast channel, in which user 1's channel is deterministic, while user 2's channel is a discrete memoryless channel. The transmitter has two independent confidential messages, each of which is intended for one of the receivers, but is kept completely secret from the other. We first establish the secrecy capacity...
An adaptable multi-level quadrature amplitude modulation (MQAM) method working in the VHF and UHF band is proposed. By estimating the channel condition, the energy of the received signal is detected, and it is compared to a threshold to control the switching between the two data-signaling rates. A novel carrier frequency offset tracking scheme is also proposed using a designed conjugate code based...
A new carrier frequency offset estimation scheme in the orthogonal frequency division multiplexing (OFDM) system is proposed. In non-data-aided synchronization systems, maximum likelihood estimation (MLE) is often used for carrier frequency offset acquisition , but it could not correct the accumulated residue frequency offset caused by sampling clock offset and other factors. After simple comparisons...
This paper analyzes and compares performances of several improved medium access control (MAC) protocols and CSMA/CA protocol when the data rate is high (at least 1 Gbps), then proposes a novel MAC protocol, called pseudo-time division backoff scheme (PTDBS). The proposed scheme can be implemented in IEEE 802.15.3c easily and it can become an improved access control method in contention access period...
Culture is a very important factor in affecting design and promoting its development, only by deeply rooted in culture could design make progress. The development of the Chinese design has to absorb Chinese culture into it. By analyzing the relationship between national culture and characteristics of design in different countries, and the relationship between Chinese culture and design, the current...
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