A fully integrated multi-standard frequency synthesizer for GNSS receivers with cellular network positioning capability

作者：Li Bin; Fan Xiangning^*; Li Wei; Zhang Li; Wang Zhigong

来源：Chinese Journal of Semiconductors, 2013, 34(1): 015002.

DOI：10.1088/1674-4926/34/1/015002

• Active area
• Cellular network
• CMOS technology
• Die area
• Different frequency
• Fractional mode
• Fractional spurs
• Fully integrated
• GALILEO
• Global Navigation Satellite Systems
• GNSS receivers
• Hardware complexity
• Loop bandwidth
• Multi-standard
• Multiband
• Phase noise performance
• Power supply
• Reference spur
• Sequence lengths
• TD-SCDMA
• TD-SCDMA standards
• Trade off
• Voltage-controlled-oscillator

A fully integrated hybrid integer/fractional frequency synthesizer is presented. With a single multiband voltage-controlled-oscillator (VCO), the frequency synthesizer can support GPS, Galileo, Compass and TD-SCDMA standards. Design is carefully performed to trade off power, die area and phase noise performance. By reconfiguring between the integer mode and fractional mode, different frequency resolution requirements and a constant loop bandwidth for each standard can be achieved simultaneously. Moreover, a long sequence length, reduced hardware complexity multi-stage-noise-shaping (MASH) Δ-Σ modulator is employed to reduce fractional spur in the fractional mode. Fabricated in a 0.18 μm CMOS technology, the frequency synthesizer occupies an active area of 1.48 mm2 and draws a current of 13.4-16.2 mA from a 1.8 V power supply. The measured phase noise is lower than -80 dBc/Hz at 100 kHz offset and -113 to -124 dBc/Hz at 1 MHz offset respectively, while the measured reference spur is -71 dBc in integer mode and the fractional spur is -65 dBc in fractional mode.

• 出版日期2013
• 单位东南大学