Jalil Jubayer, Reaz Mamun Bin Ibne, Bhuiyan Mohammad Arif Sobhan, Rahman Labonnah Farzana, Chang Tae Gyu
Department of Electrical, Electronic and Systems Engineering, Universiti Kebangsaan Malaysia, 43600 UKM, Bangi, Selangor, Malaysia.
School of Electrical and Electronics Engineering, Chung-Ang University, Seoul 156-756, Republic of Korea.
ScientificWorldJournal. 2014 Jan 22;2014:580385. doi: 10.1155/2014/580385. eCollection 2014.
In radio frequency identification (RFID) systems, performance degradation of phase locked loops (PLLs) mainly occurs due to high phase noise of voltage-controlled oscillators (VCOs). This paper proposes a low power, low phase noise ring-VCO developed for 2.42 GHz operated active RFID transponders compatible with IEEE 802.11 b/g, Bluetooth, and Zigbee protocols. For ease of integration and implementation of the module in tiny die area, a novel pseudodifferential delay cell based 3-stage ring oscillator has been introduced to fabricate the ring-VCO. In CMOS technology, 0.18 μm process is adopted for designing the circuit with 1.5 V power supply. The postlayout simulated results show that the proposed oscillator works in the tuning range of 0.5-2.54 GHz and dissipates 2.47 mW of power. It exhibits a phase noise of -126.62 dBc/Hz at 25 MHz offset from 2.42 GHz carrier frequency.
在射频识别（RFID）系统中，锁相环（PLL）的性能下降主要是由于压控振荡器（VCO）的高相位噪声所致。本文提出了一种为工作在2.42 GHz的有源RFID应答器开发的低功耗、低相位噪声环形VCO，该应答器与IEEE 802.11 b/g、蓝牙和Zigbee协议兼容。为便于该模块在微小芯片面积中集成和实现，引入了一种基于新型伪差分延迟单元的三级环形振荡器来制造环形VCO。在CMOS技术中，采用0.18μm工艺设计该电路，电源电压为1.5V。布局后仿真结果表明，所提出的振荡器工作在0.5 - 2.54 GHz的调谐范围内，功耗为2.47 mW。在偏离2.42 GHz载波频率25 MHz处，其相位噪声为-126.62 dBc/Hz。
