高频压控振荡器外文翻译

Voltage control design of high frequency LC oscillators

Student : Pxxx, physics and information engineering colleges

Instructor : xxx, Jianghan University

In recent years,with the rapid development of wireless communication technology, make the market for rf integrated circuit has had a huge demand. In the rf circuit, the voltage control oscillation (VCO) occupied a very important position.With a wide range of applications.In the early stages of the radio technology development,it is used to produce high-frequency in transmitter carrier voltage,As a specialized superheterodyne receivers in the machine oscillator, be sending and receiving equipment basic components.Now the use of oscillator is more and more widely.For example: in radio communication, radio, and television equipment used to produce the need of the carrier and the machine oscillation signal;In the electronic measuring instruments used to produce all sorts of frequency sine signals, etc.

Definition

Oscillator is simply stated a frequency source, usually in a phase lock loop.Detailed said is that a device don't need the signal to their own motivation, Dc power can be transformed into Ac power .Generally fall into the positive feedback and negative resistance.The so-called "oscillating",Its meaning is to allude to exchange,.Oscillator includes a never oscillation to process and function of oscillation.Can completion from dc to ac power transformation,This device can be called "oscillator".

Oscillator working principle

LC circuit consisting of capacitors and inductors, electric field and the conversion of magnetic energy production process free oscillation. To maintain the oscillation also has a positive feedback amplifier circuit, the LC oscillator is divided into a transformer coupled and three-point oscillator, many applications of quartz crystal quartz crystal oscillator, LC oscillator with an integrated operational amplifier. Exactly the same device can not be parameters in the state of the power the moment the two transistor occurs a change, this change due to increasingly strong role in the positive feedback, leading to reach a temporary steady state. During the temporary steady state to another transistor by capacitance gradually

charge conduction or closed state of the flip to another temporary steady state. This cycle of formation of oscillation.

The classification of oscillator

Oscillator are divided into RC, LC oscillators and crystal oscillator,1. The RC oscillator Use the RC network as frequency selective phase shifting network is called RC sinusoidal oscillator Belong to audio oscillator. 2. LC oscillators Use the LC oscillation loop as move and frequency selective network of Positive feedback oscillator is called LC oscillators. LC oscillators classification: (1) transformer coupling Single pipe LC sinusoidal oscillator difference to the LC sinusoidal oscillator (2) Three point pattern Condenser three point pattern oscillator, three point type oscillator (3)The improvement of three type Clapp oscillator, Seiler oscillator (4)The difference of tube oscillator 3.Crystal oscillator The oscillation frequency of the oscillator by quartz crystal controlled oscillator.

The temperature coefficient oscillator

Temperature coefficient oscillator refers to an oscillator, its oscillation frequency and temperature have a specific relationship between the different temperatures corresponding to different oscillation frequencies. Conversely, measuring the output frequency of the oscillator, we can measure the temperature. High temperature coefficient oscillator: its oscillation frequency is affected by temperature, a slight change in temperature, the frequency will change a lot, that is temperature sensitive, and more for the temperature sensor. low temperature coefficient oscillator: the oscillation frequency temperature has little effect, even if the temperature varies greatly, its frequency is essentially the same.

Quartz crystal oscillator

Quartz crystal oscillator and non-temperature compensated crystal oscillators, temperature compensated crystal oscillator (TCXO), voltage controlled crystal oscillator (VCXO), thermostatically controlled crystal oscillator (OCXO) and digital / μp compensated crystal oscillator (DCXO / MCXO) and other types. Among them, temperature compensated crystal oscillator is the simplest one, in the Japanese Industrial Standard (JIS), called the standard package crystal oscillator (SPXO). Now SPXO example, a brief overview of the structure and working principle of the quartz crystal oscillator.