This paper reviews several techniques used to reduce the in-band phase noise contribution of fractional-N frequency synthesizers. The paper develops several practical techniques for specifying the noise and linearity of components used in a fractional-N synthesizer. As an example, it presents a synthesizer with an in-band phase noise floor of 97 dBc/Hz@10 KHz for an RF output frequency of 2.432...

The design of frequency synthesizers is especially challenging for wireless applications due to the requirements for high spectral purity, high frequency range, and fast tuning together with reasonable power consumption. In this paper, the idea of combining digital and analog techniques for achieving these goals is discussed. The proposed architecture uses I/Q modulation to translate a digitall...

This paper presents the JD-1, a digital controller for analog modular synthesizers. The JD-1 features a capacitive touchsensing keyboard that responds to continuous variations in finger contact, high-accuracy polyphonic control-voltage outputs, a built-in sequencer, and digital interfaces for connection to MIDI and OSC devices. Design goals include interoperability with a wide range of synthesi...

Broadband metrological-grade frequency comb (FC) synthesizers with a rich number of phase locked modes are the ideal sources for quantum sensing and metrology. At terahertz (THz) frequencies, electrically pumped cascade lasers (QCLs) have shown quantum-limited noise operation, phase/frequency absolute referencing self-starting FC albeit over rather restricted dynamic range, governed by nature g...

This work proposes a novel pre-distortion technique for the quantization noise cancellation of fractional-N frequency synthesizers. The proposed technique utilizes the coordinate rotation digital computer (CORDIC) algorithm to pre-distort the baseband signal of a wireless system with the quantization noise. The pre-distorted signal then modulates the noisy output signal of the fractional-N freq...

Here are.two broadband, programmable, high-spectral-purity microwave signal sources, a 2-to-1 8-GHz synthesized signal generator and a 2-to-6.2-GHz synthesizer. Both are single, compact, 13-cm-high instruments. tr REQUENCY SYNTHESIZERS are signal sources l' that produce a selected output frequency by some type of arithmetic operation on a stable reference signal, which is usually derived from a...

A radiation-hardened 12-bit non-linear DAC was designed and fabricated on Honeywell’s 0.35 μm MOI5 SOI CMOS process. The non-linear DAC allows a significant reduction in complexity and power dissipation when used within direct digital frequency synthesizers (DDFSs). The non-linear DAC implements a 32-segement piecewise linear approximation to sine function reducing the ROM look-up table size fr...

has been planning for the influx of digital and Coding, " Bell System Tech. Abstract-Several aspects of the design of digital frequency synthesizers are considered, and a detailed analysis of the spectral purity of digitally synthesized frequencies is given. These results are then applied to a specific application: the testing of A/D and D/A converters. F REQUENCY synthesis, which is the proces...