In this paper we present an optimized trellis coded vector quantization (TCVQ) coding system designed for the effective and robust coding of LSF spectral parameters at low bit rate. The aim of this system, called at t...
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In this paper we present an optimized trellis coded vector quantization (TCVQ) coding system designed for the effective and robust coding of LSF spectral parameters at low bit rate. The aim of this system, called at the beginning << LSF-OTCVQ Encoder >>, is to achieve a low bit rate transparent quantization of LSF parameters of the US Federal Standard (FS1016) speech coder. Once the effectiveness of our LSF-OTCVQ encoders (with weighted distance) was proven in the case of ideal transmissions over noiseless channel, we were interested after in the improvement of their robustnesses for real transmissions over noisy channel. To implicitly protect the transmission indices of our LSF-OTCVQ coders incorporated in the FS1016, we used a joint source-channel coding carried out by the channel optimized vector quantization (CONQ) method. In the case of transmissions over noisy channel, we will show that our new encoding system, called "COVQ-LSF-OTCVQ Encoder", would be able to contribute significantly in the improvement of the FS1016 performances by ensuring a good coding robustness of its LSF spectral parameters.
In this paper, we analyze the performance of multilevel coding for high level QAM constellations. After the presentation of the encoder principle, we focus our study on a sub-optimal decoder which can be implemented v...
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In this paper, we analyze the performance of multilevel coding for high level QAM constellations. After the presentation of the encoder principle, we focus our study on a sub-optimal decoder which can be implemented very simply. We analyze the performance of the presented technique in terms of asymptotic gain and bit error rate characteristics. Finally, a practical application in digital microwave radio links is considered, and one- and two-level coded 128-QAM are studied. At a bit error rate of 10(-8), it is shown that a 4 dB coding gain can be reached with moderate decoder complexity. These coding schemes are therefore very attractive for high-capacity microwave links applications.
In this paper, it is shown that a parallel approach for CRC coding can be derived for a number of bits less than, or equal to, the degree of the code generator polynomial, or for larger values as well. In both cases i...
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In this paper, it is shown that a parallel approach for CRC coding can be derived for a number of bits less than, or equal to, the degree of the code generator polynomial, or for larger values as well. In both cases if formulas are different, the logic diagrams are very similar and corresponding circuits are prone to efficient VLSI integration.
According to the characteristics and requirements of NCT processing system, deeper research was done on the system. The three-module design has been completed based on motion controller. The first module is completed ...
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ISBN:
(纸本)9783037856482
According to the characteristics and requirements of NCT processing system, deeper research was done on the system. The three-module design has been completed based on motion controller. The first module is completed on the design of panel, key position, machine functions and coding circuit;the second module is mainly accomplished on the tool-path generation, tool adapter and program development;the last module is used to verify the NC codes. Thus the NCT processing system is improved effectively.
To meet the requirements of missile's high maneuverability and high hit rate, we have designed a new-type missile's mathematical model. This design has realized the missile's rapid tracking and control. It...
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ISBN:
(纸本)9781424472352
To meet the requirements of missile's high maneuverability and high hit rate, we have designed a new-type missile's mathematical model. This design has realized the missile's rapid tracking and control. It has the advantages of analyzing target rapidly. There are two essential features in this design: one is that only hardware circuits used in this design, this not only can prevent jamming signal, but also improve the responding ability;another is that it not only has the ability of video detecting and tracking, but also has the ability of recognizing image information and detecting hidden.
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