A 2.4GHz ASK transmitter suitable for a low power wireless capsule endoscope system is presented. A mixer-based frequency up-conversion transmitter architecture is employed to achieve a high data rate. A pseudodiffere...A 2.4GHz ASK transmitter suitable for a low power wireless capsule endoscope system is presented. A mixer-based frequency up-conversion transmitter architecture is employed to achieve a high data rate. A pseudodifferential stacked class-A power amplifier using the current reuse technique is proposed to save power. The transmitter mainly includes two parts： a 20MHz ASK modulator based on a constant amplitude phase lock loop （PLL） and a direct up-conversion RF circuit. This design, implemented in a TSMC 0.25μm CMOS process, achieves a - 23. 217dBm output power with a data rate of 1Mbps and dissipates 3.17mA of current with a single 2.5V power supply.展开更多
The transmission characteristics of the optical label switching system based on the FSK/ASK orthogonal modulation format is investigated. The factors that affect the transmission performance, such as the FSK tone spac...The transmission characteristics of the optical label switching system based on the FSK/ASK orthogonal modulation format is investigated. The factors that affect the transmission performance, such as the FSK tone space, dispersion compensation and coupler split ratio, are studied by numerical simulation. The proposed scheme is also experimentally demonstrated with a transmission of 155 Mbit/s FSK label combined with 10 Gbit/s ASK payload.展开更多
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
文摘A 2.4GHz ASK transmitter suitable for a low power wireless capsule endoscope system is presented. A mixer-based frequency up-conversion transmitter architecture is employed to achieve a high data rate. A pseudodifferential stacked class-A power amplifier using the current reuse technique is proposed to save power. The transmitter mainly includes two parts： a 20MHz ASK modulator based on a constant amplitude phase lock loop （PLL） and a direct up-conversion RF circuit. This design, implemented in a TSMC 0.25μm CMOS process, achieves a - 23. 217dBm output power with a data rate of 1Mbps and dissipates 3.17mA of current with a single 2.5V power supply.
基金supported by the National Natural Science Foundation of China(Grant No 60677004)the National High Technology Research and Development Program of China(Grant No 2007AA01Z260)+4 种基金The project is also supported by the Key Project of Chinese Ministry of Education(Grant No 107011)the Key Laboratory of Broadband Optical Fiber Transmission and Communication Networks(UESTC)(Ministry of Education of China)Teaching and Scientific Research Foundation for the Returned Overseas Chinese Scholars(State Education Ministry of China)the Corporative Building Project of Beijing Educational Committee(Grant No XK100130737)the Program for New Century Excellent Talents in University of China(Grant No NECT-07-0111)
文摘The transmission characteristics of the optical label switching system based on the FSK/ASK orthogonal modulation format is investigated. The factors that affect the transmission performance, such as the FSK tone space, dispersion compensation and coupler split ratio, are studied by numerical simulation. The proposed scheme is also experimentally demonstrated with a transmission of 155 Mbit/s FSK label combined with 10 Gbit/s ASK payload.
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.
