An Optimized AS Modulator in Fractional-N Frequency Synthesizer for UHF RFID Reader
A 3rd-order 3-bit single-loop Δ∑ modulator in fractional-N frequency synthesizer for UHF RFID Reader is optimized in terms of phase noise. Feed forward and feedback path structure is proposed in the Δ∑ modulator. The location of zeros and poles are placed at desired frequency for noise shaping by configuring feed forward and feedback coefficients. A fully integrated Δ∑ fractional-N frequency synthesizer with digital Δ∑ modulator is implemented in 0.18μm CMOS technology. The measured phase noise of the proposed Δ∑ fractional-N frequency synthesizer is 76dBc/Hz in-band and -125dBc/Hz at 1MHz offset from 856 MHz carrier and a loop bandwidth of 50 kHz. The rms jitter is 6.74ps and the integrated phase noise is 2.08° from 10kHz to 10MHz frequency offset.
Chunqi Shi Runxi Zhang Lei Chen Zongsheng Lai
East China Normal University, Shanghai, China
国际会议
成都
英文
1468-1471
2010-05-08(万方平台首次上网日期,不代表论文的发表时间)