A novel ASIC design of changeable-point digital pulse compression (DPC) chip is presented. System hardware resource is reduced to one third of the traditional design method through operations sharing hardware, (i.e.) ...A novel ASIC design of changeable-point digital pulse compression (DPC) chip is presented. System hardware resource is reduced to one third of the traditional design method through operations sharing hardware, (i.e.) let FFT, complex multiplication and IFFT be fulfilled with the same hardware structure. Block-floating-point scaling is used to enhance the dynamic range and computation accuracy. This design applies parallel pipeline structure and the radix-4 butterfly operation to improve the processing speed. In addition, a triple-memory-space(TMS) configuration is used that allows input, computation and output operations to be overlapped, so that the dual-butterfly unit is never left in an idle state waiting for I/O operation. The whole design is implemented with only one chip of XC2V500-5 FPGA. It can implement 1 024-point DPC within 91 6 μs.The output data is converted to floating-point formation to achieve seamless interface with TMS320C6701. The validity of the design is verified by simulation and measurement results.展开更多
Since Pulse Code Modulation emerged in 1937, digitized speech has experienced rapid development due to its outstanding voice quality, reliability, robustness and security in communication. But how to reduce channel wi...Since Pulse Code Modulation emerged in 1937, digitized speech has experienced rapid development due to its outstanding voice quality, reliability, robustness and security in communication. But how to reduce channel width without loss of speech quality remains a crucial problem in speech coding theory. A new full-duplex digital speech communication system based on the Vocoder of AMBE-1000(TM) and microcontroller ATMEL 89C51 is introduced. It shows higher voice quality than current mobile phone system with only a quarter of channel width needed for the latter. The prospective areas in which the system can be applied include satellite communication, IP Phone, virtual meeting and the most important, defence industry.展开更多
A new method which employs compressive sensing(CS) to reconstruct the sparse spectrum is designed and experimentally demonstrated. On the basis of CS theory, the simulation results indicate that the probability of rec...A new method which employs compressive sensing(CS) to reconstruct the sparse spectrum is designed and experimentally demonstrated. On the basis of CS theory, the simulation results indicate that the probability of reconstruction is high when the step of the sparsity adaptive matching pursuit algorithm is confirmed as 1. Contrastive analysis for four kinds of commonly used measurement matrices: part Hadamard, Bernoulli, Toeplitz and Circular matrix, has been conducted. The results illustrate that the part Hadamard matrix has better performance of reconstruction than the other matrices. The experimental system of the spectral compression reconstruction is mainly based on the digital micro-mirror device(DMD). The experimental results prove that CS can reconstruct sparse spectrum well under the condition of 50% sampling rate. The system error 0.0781 is obtained, which is defined by the average value of the 2-norm. Furthermore, the proposed method shows a dominant ability to discard redundancy.展开更多
文摘A novel ASIC design of changeable-point digital pulse compression (DPC) chip is presented. System hardware resource is reduced to one third of the traditional design method through operations sharing hardware, (i.e.) let FFT, complex multiplication and IFFT be fulfilled with the same hardware structure. Block-floating-point scaling is used to enhance the dynamic range and computation accuracy. This design applies parallel pipeline structure and the radix-4 butterfly operation to improve the processing speed. In addition, a triple-memory-space(TMS) configuration is used that allows input, computation and output operations to be overlapped, so that the dual-butterfly unit is never left in an idle state waiting for I/O operation. The whole design is implemented with only one chip of XC2V500-5 FPGA. It can implement 1 024-point DPC within 91 6 μs.The output data is converted to floating-point formation to achieve seamless interface with TMS320C6701. The validity of the design is verified by simulation and measurement results.
文摘Since Pulse Code Modulation emerged in 1937, digitized speech has experienced rapid development due to its outstanding voice quality, reliability, robustness and security in communication. But how to reduce channel width without loss of speech quality remains a crucial problem in speech coding theory. A new full-duplex digital speech communication system based on the Vocoder of AMBE-1000(TM) and microcontroller ATMEL 89C51 is introduced. It shows higher voice quality than current mobile phone system with only a quarter of channel width needed for the latter. The prospective areas in which the system can be applied include satellite communication, IP Phone, virtual meeting and the most important, defence industry.
基金supported by the National Natural Science Foundation of China(Nos.61002013 and 11504435)the Natural Science Foundation of Hubei Province(No.2014CFA051)+1 种基金the Key Technology R&D Program of Hubei Province(No.2015BCE048)the Fundamental Research Funds for the Central Universities,South-Central University for Nationalities(Nos.CZY13034,CZW15055 and CZP17026)
文摘A new method which employs compressive sensing(CS) to reconstruct the sparse spectrum is designed and experimentally demonstrated. On the basis of CS theory, the simulation results indicate that the probability of reconstruction is high when the step of the sparsity adaptive matching pursuit algorithm is confirmed as 1. Contrastive analysis for four kinds of commonly used measurement matrices: part Hadamard, Bernoulli, Toeplitz and Circular matrix, has been conducted. The results illustrate that the part Hadamard matrix has better performance of reconstruction than the other matrices. The experimental system of the spectral compression reconstruction is mainly based on the digital micro-mirror device(DMD). The experimental results prove that CS can reconstruct sparse spectrum well under the condition of 50% sampling rate. The system error 0.0781 is obtained, which is defined by the average value of the 2-norm. Furthermore, the proposed method shows a dominant ability to discard redundancy.
