We experimentally demonstrate a 750 Mb/s real-time visible light communication（VLC） system based on non-return-to-zero on–off keying modulation by employing single commercially available monochromatic lightemitting...We experimentally demonstrate a 750 Mb/s real-time visible light communication（VLC） system based on non-return-to-zero on–off keying modulation by employing single commercially available monochromatic lightemitting diodes. To enhance the 3-d B bandwidth of the VLC link, we propose a low-complexity cascaded post-equalizer based on NPN transistors. With two different frequency-selecting networks in our post-equalizer,the highest achieved 3-d B bandwidth of the VLC link is 370 MHz. The highest achieved data rate is 750 Mb/s at a communication distance of 170 cm with a bit error rate below 1 × 10^（-6）, which is far below the forward error correction limit（3.8 × 10^（-3））. Based on our monochromatic VLC system, a wavelength-division multiplexing VLC system could be designed with a higher data rate.展开更多
We propose a two-cascaded, constant-resistance, symmetrical bridged-T amplitude equalizer for a high-speed visible light communication（VLC） system. With the pre-equalization circuit, the-3 d B bandwidth of the VLC s...We propose a two-cascaded, constant-resistance, symmetrical bridged-T amplitude equalizer for a high-speed visible light communication（VLC） system. With the pre-equalization circuit, the-3 d B bandwidth of the VLC system can be extended from 12 to 235 MHz using a commercially available phosphorescent white light-emitting diode（LED）, a blue filter, and a low-cost PIN photodiode. The data rate is 1.20 Gbit/s, exploiting 16-quadrature amplitude modulation-orthogonal frequency-division multiplexing with a 300 MHz modulation bandwidth over50 cm of free-space transmission under the pre-forward error correction limit of 3.8 × 10^-3. To our knowledge,this is the highest-3 d B bandwidth and the highest data rate ever achieved by using a pre-equalization circuit and white LED in a VLC system.展开更多
The paper review the public-key cryptosystems based on the error correcting codes such as Goppa code, BCH code, RS code, rank distance code, algebraic geometric code as well as LDPC code, and made the comparative anal...The paper review the public-key cryptosystems based on the error correcting codes such as Goppa code, BCH code, RS code, rank distance code, algebraic geometric code as well as LDPC code, and made the comparative analyses of the merits and drawbacks of them. The cryptosystem based on Goppa code has high security, but can be achieved poor. The cryptosystems based on other error correcting codes have higher performance than Goppa code. But there are still some disadvantages to solve. At last, the paper produce an assumption of the Niederreiter cascade combination cryptosystem based on double public-keys under complex circumstances, which has higher performance and security than the traditional cryptosystems.展开更多
基金supported by the National 973 Project of China(No.2013CB329202)the National Natural Science Foundation of China(No.61571067)
文摘We experimentally demonstrate a 750 Mb/s real-time visible light communication（VLC） system based on non-return-to-zero on–off keying modulation by employing single commercially available monochromatic lightemitting diodes. To enhance the 3-d B bandwidth of the VLC link, we propose a low-complexity cascaded post-equalizer based on NPN transistors. With two different frequency-selecting networks in our post-equalizer,the highest achieved 3-d B bandwidth of the VLC link is 370 MHz. The highest achieved data rate is 750 Mb/s at a communication distance of 170 cm with a bit error rate below 1 × 10^（-6）, which is far below the forward error correction limit（3.8 × 10^（-3））. Based on our monochromatic VLC system, a wavelength-division multiplexing VLC system could be designed with a higher data rate.
基金supported by the National Natural Science Foundation of China (No. 61177071)the National "863" Program of China (No. 2013AA013603)
文摘We propose a two-cascaded, constant-resistance, symmetrical bridged-T amplitude equalizer for a high-speed visible light communication（VLC） system. With the pre-equalization circuit, the-3 d B bandwidth of the VLC system can be extended from 12 to 235 MHz using a commercially available phosphorescent white light-emitting diode（LED）, a blue filter, and a low-cost PIN photodiode. The data rate is 1.20 Gbit/s, exploiting 16-quadrature amplitude modulation-orthogonal frequency-division multiplexing with a 300 MHz modulation bandwidth over50 cm of free-space transmission under the pre-forward error correction limit of 3.8 × 10^-3. To our knowledge,this is the highest-3 d B bandwidth and the highest data rate ever achieved by using a pre-equalization circuit and white LED in a VLC system.
基金Supported by the Postgraduate Project of Military Science of PLA(2013JY431)55th Batch of China Postdoctoral Second-Class on Fund Projects(2014M552656)
文摘The paper review the public-key cryptosystems based on the error correcting codes such as Goppa code, BCH code, RS code, rank distance code, algebraic geometric code as well as LDPC code, and made the comparative analyses of the merits and drawbacks of them. The cryptosystem based on Goppa code has high security, but can be achieved poor. The cryptosystems based on other error correcting codes have higher performance than Goppa code. But there are still some disadvantages to solve. At last, the paper produce an assumption of the Niederreiter cascade combination cryptosystem based on double public-keys under complex circumstances, which has higher performance and security than the traditional cryptosystems.
