In the paper, a programmable phase-locked loop (PLL) based ISM band fractional-N frequency synthesizer, commonly used in wireless communication system, is presented. The third order error-feedback Delta-Sigma modulator and high linearity offset phase frequency detector (PFD)/ Charge Pump (CP) are adopted to reduce close-in phase noise due to ∆Σ quantization noise folding. Automatic calibration ...

The main function of a frequency synthesizer is to deliver a stable and clean signal. However, many applications require not only a fixed frequency signal but also various modulation functions ranging from simple pulse, amplitude, frequency and phase modulation to complex digital modulation formats. Although modulators are usually realized as external devices, they can also be incorporated into...

Design of Compact Frequency Synthesizer for Self-Calibration in RF Circuits. (August 2004) Sanghoon Park, B.S., Korea University, Seoul, Republic of Korea Chair of Advisory Committee: Dr. Aydin Ilker Karsilayan A compact frequency synthesizer based on a phase locked loop (PLL) is designed for the self-calibration in RF circuits. The main advantage of the presented frequency synthesizer is that ...

GSM & EDGE base-stations require synthesizers that can frequency hop over the full 75MHz TX or RX band in < 10us and also have very low phase noise and spurious. To date, these conflicting requirements can only be accomplished using a costly "ping-pong" architecture where one synthesizer is locking to the next desired frequency while the other is active as the LO. The proposed fast switching sy...

Frequency synthesis is one of the most important and most actively researched subjects in the field of VLSI mixed-signal circuit design. Among the existing techniques in this area, phase locked loop fractional architecture is a widely used one for generating frequencies which are not integer multiple of the input reference frequency. Flying-Adder architecture is an emerging technique which is b...

This paper presents a Wireless-USB/WiMedia-compliant fast-hopping frequency synthesizer architecture with quadrature outputs based on sub-harmonic injection-locking. The synthesizer features a cross-coupled quadrature digitally-controlled oscillator, that is injection-locked to a sub-harmonic frequency. An intuitive closed-form expression for the dynamics of the quadrature injection-locked osci...