Free space optical communication (FSO) proves to be very effective and efficient technology for wireless communication. This work basically deals with the designing of FSO systems. Further, a comparative study has bee...Free space optical communication (FSO) proves to be very effective and efficient technology for wireless communication. This work basically deals with the designing of FSO systems. Further, a comparative study has been made to ascertain which modulation technique proves better for communication. This paper investigates the performance of ASK and PSK modulation based FSO system by varying different FSO parameters under several conditions including haze, rain, mist and fog. Finally, simulation results are analysed and discussed.展开更多
早期近距离无线通信技术(near field communication,NFC)标准规定13.56 MHz无线通信卡的数据速率最高到848 Kbps,在智能手机NFC技术广泛应用的背景下,通信要求达到超高数据速率(very high bit rate,VHBR)。近场通信卡(proximity integra...早期近距离无线通信技术(near field communication,NFC)标准规定13.56 MHz无线通信卡的数据速率最高到848 Kbps,在智能手机NFC技术广泛应用的背景下,通信要求达到超高数据速率(very high bit rate,VHBR)。近场通信卡(proximity integrated circuit card,PICC)接收电路数据速率提升的难点主要在于移幅键控法/移频键控法(amplitude-shift keying/phase-shift keying,ASK/PSK)接收器的设计,其在实际应用中受码间串扰(inter-symbol interference,ISI)、功耗、电路复杂度等限制。针对以上问题,提出一种完整的低功耗PICC解调解码电路设计,包含高定时精度的全数字定时恢复电路。设计实现采用标准0.18μm互补金属氧化物半导体(complementary metal oxide semiconductor,CMOS)工艺,实现了147 pJ/bit的能效,可应用于ASK 0.106~3.39 Mbps数据速率通信。展开更多
A novel optical return zero differential quadrature phase shifted keying/inverse return zero amplitude shifted keying （RZ-DQPSFUIRZ-ASK） orthogonal modulation format scheme for all-optical label swapping is analyzed...A novel optical return zero differential quadrature phase shifted keying/inverse return zero amplitude shifted keying （RZ-DQPSFUIRZ-ASK） orthogonal modulation format scheme for all-optical label swapping is analyzed theoretically and experimentally. The transmission characteristics of RZ-DQPSK/IRZ-ASK modulation format transmission system are demonstrated. Results show that high extinction ratio is obtained for IRZ-ASK label signal while at the same time the all-optical label swapping, differential quadrature phase shifted keying （DQPSK） payload signal is hardly affected. It requires only 0.9 dB higher power penalty compared to 21.4 Gbit/s RZ-DQPSK modulation format and less than 2 dB transmission penalty after 60 km. The proposed scheme is a practical solution for meeting the data rate and cost-efficiency of the optical links simultaneously in future all-optical label swapping.展开更多
文摘Free space optical communication (FSO) proves to be very effective and efficient technology for wireless communication. This work basically deals with the designing of FSO systems. Further, a comparative study has been made to ascertain which modulation technique proves better for communication. This paper investigates the performance of ASK and PSK modulation based FSO system by varying different FSO parameters under several conditions including haze, rain, mist and fog. Finally, simulation results are analysed and discussed.
文摘早期近距离无线通信技术(near field communication,NFC)标准规定13.56 MHz无线通信卡的数据速率最高到848 Kbps,在智能手机NFC技术广泛应用的背景下,通信要求达到超高数据速率(very high bit rate,VHBR)。近场通信卡(proximity integrated circuit card,PICC)接收电路数据速率提升的难点主要在于移幅键控法/移频键控法(amplitude-shift keying/phase-shift keying,ASK/PSK)接收器的设计,其在实际应用中受码间串扰(inter-symbol interference,ISI)、功耗、电路复杂度等限制。针对以上问题,提出一种完整的低功耗PICC解调解码电路设计,包含高定时精度的全数字定时恢复电路。设计实现采用标准0.18μm互补金属氧化物半导体(complementary metal oxide semiconductor,CMOS)工艺,实现了147 pJ/bit的能效,可应用于ASK 0.106~3.39 Mbps数据速率通信。
基金supported by the National Basic Research Program of China (2003CB314901)the Hi-Tech Research and Development Project of China (2006AA03Z416,2007AA03Z418)+2 种基金the National Natural Science Foundation of China (60576018)the 111 Project (B07005)the Program for Changjiang Scholars and Innovative Research Team in University,MOE
文摘A novel optical return zero differential quadrature phase shifted keying/inverse return zero amplitude shifted keying （RZ-DQPSFUIRZ-ASK） orthogonal modulation format scheme for all-optical label swapping is analyzed theoretically and experimentally. The transmission characteristics of RZ-DQPSK/IRZ-ASK modulation format transmission system are demonstrated. Results show that high extinction ratio is obtained for IRZ-ASK label signal while at the same time the all-optical label swapping, differential quadrature phase shifted keying （DQPSK） payload signal is hardly affected. It requires only 0.9 dB higher power penalty compared to 21.4 Gbit/s RZ-DQPSK modulation format and less than 2 dB transmission penalty after 60 km. The proposed scheme is a practical solution for meeting the data rate and cost-efficiency of the optical links simultaneously in future all-optical label swapping.
