为了降低可见光通信(VLC)系统的误码率,设计了一种基于二进制开关键控(OOK)调制的VLC视频传输系统。该系统采用改进型4B5B编码、后均衡放大电路改善了系统误码性能,拓展了系统的-3 d B带宽,并在自适应阈值判决的基础上分析数据的相关性...为了降低可见光通信(VLC)系统的误码率,设计了一种基于二进制开关键控(OOK)调制的VLC视频传输系统。该系统采用改进型4B5B编码、后均衡放大电路改善了系统误码性能,拓展了系统的-3 d B带宽,并在自适应阈值判决的基础上分析数据的相关性特征,实现了OOK解调。实验结果表明:系统可以在2 m的距离下实现1080 P高清视频的实时、无失真传输;当传输速率为60 Mb/s时,改进型4B5B编码能将系统无编码时的误码率由2.2×10^(-2)降低至2.81×10^(-6)。展开更多
A 2.4 GHz ultra-low-power RF transceiver with a 900 MHz auxiliary wake-up link for wireless body area networks（WBANs）in medical applications is presented.The RF transceiver with an asymmetric architecture is propose...A 2.4 GHz ultra-low-power RF transceiver with a 900 MHz auxiliary wake-up link for wireless body area networks（WBANs）in medical applications is presented.The RF transceiver with an asymmetric architecture is proposed to achieve high energy efficiency according to the asymmetric communication in WBANs.The transceiver consists of a main receiver（RX）with an ultra-low-power free-running ring oscillator and a high speed main transmitter（TX）with fast lock-in PLL.A passive wake-up receiver（WuRx）for wake-up function with a high power conversion efficiency（PCE）CMOS rectifier is designed to offer the sensor node the capability of work-on-demand with zero standby power.The chip is implemented in a 0.18μm CMOS process.Its core area is 1.6 mm^2. The main RX achieves a sensitivity of-55 dBm at a 100 kbps OOK data rate while consuming just 210μA current from the 1 V power supply.The main TX achieves ＋3 dBm output power with a 4 Mbps/500 kbps/200 kbps data rate for OOK/4 FSK/2 FSK modulation and dissipates 3.25 mA/6.5 mA/6.5 mA current from a 1.8 V power supply. The minimum detectable RF input energy for the wake-up RX is-15 dBm and the PCE is more than 25%.展开更多
A 2.4 GHz high efficiency radio frequency （RF） transmitter for wireless body area network （WBAN） in medical applications is presented in this paper. The transmitter architecture with high energy efficiency is prop...A 2.4 GHz high efficiency radio frequency （RF） transmitter for wireless body area network （WBAN） in medical applications is presented in this paper. The transmitter architecture with high energy efficiency is proposed to achieve a high data rate with low power consumption. In conventional transmitters, the oscillator and power amplifier are turned off when the transmitter sends 0. The required time for turning oscillator ON/OFF is longer than the other blocks of the transmitter. In the proposed transmitter, the low power oscillator is on all the time while the power amplifier and modulator are turned off when＂0＂data is sent. The transmitter consumes 3.2 mW at 0.5 dBm output by 285 Mbps data rate and the energy consumption per transmitted bit with 0.5 dBm output power is 10 pJ/（bit-mW）. The proposed transmitter was designed in 0.18 μm CMOS technology.展开更多
In this paper, the performance evaluation of Frequency Modulated Chaotic On-Off Keying (FM-COOK) in AWGN, Rayleigh and Rician fading channels is given. The simulation results show that an improvement in BER can be gai...In this paper, the performance evaluation of Frequency Modulated Chaotic On-Off Keying (FM-COOK) in AWGN, Rayleigh and Rician fading channels is given. The simulation results show that an improvement in BER can be gained by incorporating the FM modulation with COOK for SNR values less than 10dB in AWGN case and less than 6dB for Rayleigh and Rician fading channels.展开更多
基金Project supported by the National High-Tech Research and Development Program of China(Nos2008AA010703,2009AA011606)the National Natural Science Foundation of China(No60976023)
文摘A 2.4 GHz ultra-low-power RF transceiver with a 900 MHz auxiliary wake-up link for wireless body area networks（WBANs）in medical applications is presented.The RF transceiver with an asymmetric architecture is proposed to achieve high energy efficiency according to the asymmetric communication in WBANs.The transceiver consists of a main receiver（RX）with an ultra-low-power free-running ring oscillator and a high speed main transmitter（TX）with fast lock-in PLL.A passive wake-up receiver（WuRx）for wake-up function with a high power conversion efficiency（PCE）CMOS rectifier is designed to offer the sensor node the capability of work-on-demand with zero standby power.The chip is implemented in a 0.18μm CMOS process.Its core area is 1.6 mm^2. The main RX achieves a sensitivity of-55 dBm at a 100 kbps OOK data rate while consuming just 210μA current from the 1 V power supply.The main TX achieves ＋3 dBm output power with a 4 Mbps/500 kbps/200 kbps data rate for OOK/4 FSK/2 FSK modulation and dissipates 3.25 mA/6.5 mA/6.5 mA current from a 1.8 V power supply. The minimum detectable RF input energy for the wake-up RX is-15 dBm and the PCE is more than 25%.
文摘A 2.4 GHz high efficiency radio frequency （RF） transmitter for wireless body area network （WBAN） in medical applications is presented in this paper. The transmitter architecture with high energy efficiency is proposed to achieve a high data rate with low power consumption. In conventional transmitters, the oscillator and power amplifier are turned off when the transmitter sends 0. The required time for turning oscillator ON/OFF is longer than the other blocks of the transmitter. In the proposed transmitter, the low power oscillator is on all the time while the power amplifier and modulator are turned off when＂0＂data is sent. The transmitter consumes 3.2 mW at 0.5 dBm output by 285 Mbps data rate and the energy consumption per transmitted bit with 0.5 dBm output power is 10 pJ/（bit-mW）. The proposed transmitter was designed in 0.18 μm CMOS technology.
文摘In this paper, the performance evaluation of Frequency Modulated Chaotic On-Off Keying (FM-COOK) in AWGN, Rayleigh and Rician fading channels is given. The simulation results show that an improvement in BER can be gained by incorporating the FM modulation with COOK for SNR values less than 10dB in AWGN case and less than 6dB for Rayleigh and Rician fading channels.
