Narrow-Band Colpitts Voltage Controlled Oscillator Design Literature
2.8 GHz Narrow-Band Colpitts Voltage Controlled Oscillator Design
Literature Survey Report
Bilkent University
Electrical&Electronics Engineering
Abstract
Oscillators are one of the main building blocks of the electronic devices. They work on the principle of oscillation which is a periodic fluctuation between the maximum and minimum value of the quantity. Oscillators mainly consist of two parts: the active circuit and the resonator. In active circuit there are active circuit elements like transistors or op-amps. Capacitors (C), Inductor (L) and resistors (R) makes the resonator and the frequency of the oscillator is determined by the resonator.
An oscillator can be designed in many ways and the main types of the oscillators are: RC Oscillator, LC Oscillator, Colpitts, Hartley, Clapp, and Pierce. The main difference of the Voltage controlled oscillator (VCO) from the other oscillator types is the oscillation frequency can be determined by the Vcont voltage. The variable capacitor (varactor) plays the main role here, if the Vcont changes than the capacitance of the varactor changes and this eventually changes the oscillation frequency. There are some crucial points that require attention while designing an oscillator: Stability, Phase Noise, Gain, Q factor, Frequency Pushing and Pulling.
In this report the brief information required to design a Colpitts VCO is given and fundamental resources books, internet sources, application and lecture notes is analyzed.
Introduction:
To be able to design a Colpitts VCO some definitions and some knowledge is required to learn. These topics and basic explanations are given;
The characteristic and analyses of Colpitts VCO;
Figure 1: Colpitts Oscillator
S-Parameters:
When there is an unknown two port network, to be able to identify what is inside of this black box we need s-parameters [4]. The figure and the explanation of the waves are given below;
Figure 2: Two port network
Then the scattering
Literature Survey Report
Bilkent University
Electrical&Electronics Engineering
Abstract
Oscillators are one of the main building blocks of the electronic devices. They work on the principle of oscillation which is a periodic fluctuation between the maximum and minimum value of the quantity. Oscillators mainly consist of two parts: the active circuit and the resonator. In active circuit there are active circuit elements like transistors or op-amps. Capacitors (C), Inductor (L) and resistors (R) makes the resonator and the frequency of the oscillator is determined by the resonator.
An oscillator can be designed in many ways and the main types of the oscillators are: RC Oscillator, LC Oscillator, Colpitts, Hartley, Clapp, and Pierce. The main difference of the Voltage controlled oscillator (VCO) from the other oscillator types is the oscillation frequency can be determined by the Vcont voltage. The variable capacitor (varactor) plays the main role here, if the Vcont changes than the capacitance of the varactor changes and this eventually changes the oscillation frequency. There are some crucial points that require attention while designing an oscillator: Stability, Phase Noise, Gain, Q factor, Frequency Pushing and Pulling.
In this report the brief information required to design a Colpitts VCO is given and fundamental resources books, internet sources, application and lecture notes is analyzed.
Introduction:
To be able to design a Colpitts VCO some definitions and some knowledge is required to learn. These topics and basic explanations are given;
The characteristic and analyses of Colpitts VCO;
Figure 1: Colpitts Oscillator
S-Parameters:
When there is an unknown two port network, to be able to identify what is inside of this black box we need s-parameters [4]. The figure and the explanation of the waves are given below;
Figure 2: Two port network
Then the scattering
References: [1] Thomas H. Lee. The design of CMOS radio-frequency integrated circuits Cambridge University Press [2] Guillermo Gonzalez. Foundations of Oscillator Circuit Design Artech House, Inc. 2007 [3] Matthew M. Radmanesh. Radio Frequency and Microwave Electronics Illustrated, Princeton Hall PTR [4] Test&Measurement Application Note 95-1, S-Parameter Techniques for Faster, More Accurate Network Design http://www.hp.com/go/tmappnotes [5] Minicircuits Application Notes http://www.minicircuits.com/pages/app_notes.html