Y. Kawano

Robust Operation of a Novel Frequency Divider Using Resonant Tunneling Chaos Circuit

We studied operating margins of the novel frequency divider using the resonant tunneling chaos circuit with respect to input signal distortions and the variations in the current-voltage characteristics of the resonant tunneling diodes (RTDs). It was shown by numerical simulation that the input signal distortions caused by harmonics which make the input signal approach the square wave and triangular wave have only a small effect on the frequency divider operation. This was confirmed using a test circuit consisting of discrete devices. Finally, it was also demonstrated by circuit simulation that this frequency divider can operate properly against the fluctuations in epitaxial growth and fabrication process conditions causing the changes of the peak to valley (p/v) current ratio and the peak current density of the RTD.

Resonant Tunneling Chaos Generator for High-Speed/Low-Power Frequency Divider

We propose a chaos generator using a resonant tunneling diode. It is a simple circuit consisting of a resonant tunneling diode, an inductor, and a capacitor. This circuit is found to output various kinds of signal patterns including chaos. The behavior of the circuit is studied by means of a bifurcation diagram. Though the chaos has several applications, we describe here the possibility of implementing a high-speed and low-power frequency divider in the bifurcation region. The operating principle is also confirmed using discrete devices.

High-Speed Operation of a Novel Frequency Divider Using Resonant Tunneling Chaos Circuit

This paper demonstrates high-frequency operations of the frequency divider IC composed of a resonant tunneling diode and a high electron mobility transistor. The maximum frequency dividing operation of 6.3 GHz was confirmed. This circuit is based on the long-period behavior of the nonlinear circuits generating chaos. We investigate the effects of the input frequency, the bias voltage, and the input amplitude on the operation to discuss the operating margins. It is also shown that the dividing ratio can be selected by changing the input amplitude.

Direct Observation of High-Frequency Chaos Signals from the Resonant Tunneling Chaos Generator

The direct observation of the chaos signal patterns in a microwave frequency range was demonstrated on the resonant tunneling chaos generator circuit. It is difficult to observe such high-frequency chaos because one must use a sampling oscilloscope. To overcome this problem, we devised a special circuit controlling the chaos to output identical signals repeatedly. This permits us to observe (seemingly)random patterns. This control scheme may lead to various applications.

Applications of high-frequency chaos in resonant tunneling chaos generator circuits

Recently, applications of chaos, which is often observed in nonlinear systems, have attracted much attention in the field of information processing and communication systems. Using RTDs to implement such nonlinear circuits has significant advantages, such as high operation frequency. In this paper, we describe some applications of resonant tunneling chaos generator circuits.

High-speed operation of a novel frequency divider using resonant tunneling chaos circuit

This paper demonstrates high-frequency operation of a frequency divider IC composed of a resonant tunneling diode and a high electron mobility transistor. This circuit is based on the long-period behavior of the nonlinear circuits generating chaos. We investigate the effects of the input frequency, the bias voltage, and the input amplitude on the operation to discuss the operating margins. It is also shown that the dividing ratio can be selected by changing the input amplitude.

Chaos generator MMIC's using resonant tunneling diodes

Recently, applications of chaos, which is often observed in nonlinear circuits, have been studied intensively in the field of information processing and communication systems. Using resonant tunneling devices to make such nonlinear circuits has many advantages, for example, simplicity in circuit, high operation frequency and low power consumption. In this paper, we report the demonstration of high-frequency operations of the chaos generator microwave monolithic ICs consisting of an RTD and a high electron mobility transistor (HEMT).

A novel frequency divider using a resonant tunneling chaos circuit

The operating principle of this frequency divider is based on a bifurcation phenomenon in non-autonomous chaos system. This has several advantages, extremely high operating frequency, low power consumption due to circuit simplicity, selectable divide ratio, and compatibility with MMIC process. The operating principle was also demonstrated using discrete devices.