WIA(Wireless Networks for Industrial Automation)是具有自主知识产权的工业自动化无线网络,它具有高可靠性、实时性、安全性等特点。本文对符合WIA-PA标准的工业无线芯片的关键技术进行研究,关注WIA-PA工业无线芯片系统架构、通信基带电路、WIA-PA协议引擎优化、安全加密、低功耗设计等方面。旨在提供符合WIA-PA标准的工业无线芯片的设计参考,为降低系统开发难度、保护相关知识产权、提高技术性能奠定坚实的基础。
This paper presents a low phase-noise fractional-N frequency synthesizer which provides an inphase/quadrature-phase(I/Q) signal over a frequency range of 220–1100 MHz for wireless networks of industrial automation(WIA) applications. Two techniques are proposed to achieve the wide range. First, a 1.4–2.2 GHz ultralow gain voltage-controlled oscillator(VCO) is adopted by using 128 tuning curves. Second, a selectable I/Q divider is employed to divide the VCO frequency by 2 or 3 or 4 or 6. Besides, a phase-switching prescaler is proposed to lower PLL phase noise, a self-calibrated charge pump is used to suppress spur, and a detect-boosting phase frequency detector is adopted to shorten settling time. With a 200 k Hz loop bandwidth, lowest measured phase noise is 106 dBc/Hz at a 10 k Hz offset and 131 dBc/Hz at a 1 MHz offset. Fabricated in the TSMC 0.18 m CMOS process, the synthesizer occupies a chip area of 1.2 mm2, consumes only 15 m W from the 1.8 V power supply,and settles within 13.2 s. The synthesizer is optimized for the WIA applications, but can also be used for other short-range wireless communications, such as 433, 868, 916 MHz ISM band applications.
This paper presents a low power, high sensitivity Gaussian frequency shift keying(GFSK) demodulator with a flexible frequency offset canceling method for wireless networks for industrial automation process automation(WIA-PA) transceiver fabricated in 0.18 m CMOS technology. The receiver uses a low-IF(1.5 MHz)architecture, and the transmitter uses a sigma delta PLL based modulation with Gaussian low-pass filter for low power consumption. The active area of the demodulator is 0.14 mm2. Measurement results show that the proposed demodulator operates without harmonic distortion, deals with˙180 k Hz frequency offset, needs SNR only 18.5 d B at 0.1% bit-error rate(BER), and consumes no more than 0.26 m A from a 1.8 V power supply.
