Silicon-based distributed voltage-controlled oscillators

Wu, Hui; Hajimiri, Ali

doi:10.1109/4.910488

Cited by 115 publications

(6 citation statements)

References 13 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…These oscillators exhibit several types of synchronization by either the nearby or global coupling and related pattern formation [1,2]. On the other hand, a typical spatially extended oscillator has been developed on an electrical transmission line with regularly spaced field-effect transistors (FETs) [3] or nonlinear varactors [4]. By utilizing small-sized devices in each section and converting the delay to charge the device parasitic capacitors into the transmission delay along the line, the operating frequency of the resulting oscillator increases.…”

Section: Introductionmentioning

confidence: 99%

Characterization of edge oscillation in a traveling-wave field-effect transistor

Narahara

2013

Phys. Rev. E

View full text Add to dashboard Cite

In this study, we characterize the oscillating pulse edges developed in a traveling-wave field-effect transistor (TWFET). Recently, it has been found that a stable shock front can develop on a TWFET, which can travel in one direction only. Once the reflected pulse edge at the far end is transmitted to the input, the shock front develops and begins to travel on the device again. This process establishes a permanent edge oscillation. This paper discusses the device setup necessary to excite such oscillations and how pulse edges oscillate on a TWFET. By applying the phase reduction scheme to the transmission equations of a TWFET, we obtain phase sensitivity, which appropriately explains the measured spatial dependence of the locking range in frequency. Moreover, multiple oscillating edges can develop simultaneously, which are mutually synchronized. The dynamics of these multiple edges are also described.

show abstract

Section: Introductionmentioning

confidence: 99%

Characterization of edge oscillation in a traveling-wave field-effect transistor

Narahara

2013

Phys. Rev. E

View full text Add to dashboard Cite

show abstract

“…The DVCO was based on a BiCMOS process and achieved a tuning range of 12% (9.3 GHz to 10.5 GHz) with a phase noise of -114 dBc/Hz at 1 MHz offset from the 10.2 GHz carrier. Moreover, a critical review of the theoretical analysis and findings was summarized in [79].…”

Section: State Of the Art In Distributed Oscillators And Vcomentioning

confidence: 99%

“…The oscillator phase noise was evaluated in [81] by identifying an effective capacitance equal to the total capacitance distributed along the transmission lines, and by accounting for the contributions of the various passive and active noise sources. In [82] a frequency domain first order distributed oscillator model is derived, with analytical treatment similar to [74] [79], and subsequently expanded to include the nonlinear noise contributions effects from each active device. The closed form expressions obtained analytically are then compared with a series of Harmonic Balance simulations using Agilent ADS © software for various distributed oscillator configurations, and demonstrating a good agreement with a maximum error of 5 dBc at 1 MHz offset.…”

Section: State Of the Art In Distributed Oscillators And Vcomentioning

confidence: 99%

“…2.19. The active devices are generally biased choosing the same gate and drain voltage level and it is kept constant, ensuring that each FET device is working in the active zone [77][78][79]. Intuitively, oscillator operation is based on the regeneration of that signal whose period results comparable with its round trip time through the closed-loop circuit, and thus dependent upon its feedback path length; the shorter it is, the higher the attainable frequency [75] becomes.…”

Section: Forward-gain Mode Distributed Oscillator Theorymentioning

confidence: 99%

“…Therefore using the formula (2.36) it can be stated that: showing that the oscillation frequency is determined by the time the signal needs to return to the starting point, completing a cycle. The real part in (2.54) determines the output voltage amplitude, as long as the relation gm= gm(Vo) is known and the bias currents Ic are kept fixed [78,79] The expression for gm(Vo)= 2Ic /Vo substituted in the first of (6.37) provides: affected, as the intuition suggests, by the losses in the line and determined by the current bias level in the output line and equivalent impedances. This oscillator is capable of being tuned by a patented method.…”

Section: Forward-gain Mode Distributed Oscillator Theorymentioning

confidence: 99%

See 2 more Smart Citations

Nonlinear simulation and design of microwave, multi-device distributed autonomous circuits

Acampora

View full text Add to dashboard Cite

It is widely believed that many drawbacks in today's wireless communication paradigm might be relieved by enabling high carrier frequency transmission, and endowing both the network and the user equipment with some degree of reconfigurability. The urgency of a new framework in wireless digital transmission which should allow for higher bit rate, lower latency and tighter delay constraints, led us to investigate the fundamental building blocks which, at the circuital/device level, will foster a change towards more efficient communication schemes, delivering a more satisfactory end user experience. Specifically, this work deals with the inherently analog devices, found at the core of each transceiver module and capable of providing the carrier signal; these are the oscillators. In particular, two distinct classes of oscillators are regarded central to our contribution. One class is constituted by N-push oscillators, which thanks to coupling effect of N identical core oscillators allow N-fold harmonic generation (and thus high frequency transmission). The second class is constituted by wideband tunable oscillators, whose topology derives from a feedback distributed amplifier and therefore called distributed oscillators; by adequately altering the bias level at each section Distributed Voltage Controlled Oscillators can be implemented (which can scan a wide frequency range). The introductory part of this work, deals with their operation principles in great detail. As microwave oscillators are nonlinear devices, a full nonlinear analysis, synthesis, and optimization is considered for their implementation. Consequently, nonlinear numerical techniques have been reviewed in the second part of the thesis. Particularly, the role of Harmonic Balance simulations and the auxiliary generator/probe method for obtaining the oscillator solutions has been emphasized; the overall research goal of this dissertation is to show that the former techniques are very effective in obtaining detailed information about the periodic steady state behavior for the two class of circuits being investigated. A triple-push oscillator topology has been initially considered. Provided a certain phase distribution is maintained among the oscillating elements, the output power of the third harmonic increases while the lower order harmonics cancel out, which represents the default operating mode. Due to circuit symmetry, to the presence of delay in the coupling network and to unavoidable mismatches, unwanted oscillating modes might coexist with the intended one. A design strategy relying on the Harmonic Balance parametric analysis of the oscillating voltage at a selected node in the coupling network with respect to coupling phase and coupling strength is presented, to the aim of quenching undesired oscillation modes. Moreover the design of a four stage reverse mode distributed voltage controlled oscillator (DVCO) has been described. All the design steps have been reported, from a very idealized, purely behavioral design to a very concrete one, involving details derived from electromagnetic simulations. Harmonic Balance techniques were used to evaluate its tuning function, output power and DC current consumption, which have been completely characterized across the tuning bandwidth. Finally, a method for an optimized design with reduced variations in the output power has been presented. An alternative implementation, targeting wider tuning ranges/ higher oscillation frequencies was introduced. The measurements performed on the fabricated prototypes revealed good agreement with the simulation results, confirming the validity of the approach.

show abstract

Oscillators

2015

Radio‐Frequency Integrated‐Circuit Engineering

View full text Add to dashboard Cite

Oscillators are always needed for radio frequency (RF) power generation, whether as a stand-alone component in RF systems or as an integral element of other components such as mixers. In contrast to amplifiers, which require stability, oscillators can work only in unstable circuit environments, which result in negative impedances enabling oscillation to occur. While RF power is an important parameter, in most typical applications, phase noise plays a more critical role; a low-phase noise is generally needed to produce a clean RF signal either for transmitters or receivers. Oscillators are typically designed as either single-ended or balanced with the latter more preferable due to possibly higher power and lower phase noise. In components or systems requiring RF power over a frequency range, voltage-controlled oscillators (VCO) are generally used. This chapter discusses the fundamentals of oscillators, the theory of phase noise, and the design of both single-ended and balanced oscillators for radio frequency integrated circuits (RFICs). PRINCIPLE OF OSCILLATIONWe consider a general oscillator circuit represented schematically as shown in Figure 12.1. The impedance Z osc (V, ) = R osc (V, ) + jX osc (V, ) represents the impedance of the indicated (active) oscillating network, consisting of active device(s) and associated circuitry, as a function of the RF voltage V produced by the active devices and frequency , and Γ osc (V, ) is the corresponding reflection coefficient. Z out ( ) = R out ( ) + jX out ( ) represents the impedance looking into the indicated (passive) output network which consists of a load or output impedance, which is typically 50 Ω, and a matching circuit that transfers the load to Z out ( ), and Γ out ( ) is the corresponding reflection coefficient. There are two possibilities for the operation of the circuit shown in Figure 12.1. They are specified as given below: Stable Operation: Stable operation occurs when Re[Z osc (V, ) + Z out ( )] > 0 (12.1) or R osc (V, ) + R out ( ) > 0 (12.2) Radio-Frequency Integrated-Circuit Engineering, First Edition. Cam Nguyen.

show abstract

Silicon-based distributed voltage-controlled oscillators

Cited by 115 publications

References 13 publications

Characterization of edge oscillation in a traveling-wave field-effect transistor

Characterization of edge oscillation in a traveling-wave field-effect transistor

Nonlinear simulation and design of microwave, multi-device distributed autonomous circuits

Oscillators

Contact Info

Product

Resources

About