What is 3rd order intercept point of an amplifier?
The third order intercept point is an important performance measure that specifies the amount of distortion inflicted on the desired signal due to the intermodulation product of two interfering signals.
What is IP3 and how do you measure it?
IP3 is the point where first-order and third-order lines cross. The process continues in this fashion. The values are read in the x or y axis. There are thus two actual values for measuring the IP point: the input or output intercept point.
Why is third order intercept important?
Why do we need to measure IP3? Calculating the Third Order Intercept is a method of quantifying intermodulation distortion (IMD) and determining the linearity of a device under test. This is important for verifying RF performance. A high IP3 value specifies that the device has good linearity.
What is P1dB and IP3?
There are two key measurements in determining power amplifier quality, efficiency, and linearity: the third-order intercept (abbreviated TOI or IP3) point and the 1-dB compression (P1dB) point. These quantities allow you to evaluate and compare amplifier specifications and performance.
What is IIP2 and IIP3?
IIP3= PIN + 1/2( Po-PIMD) Second Order Intercept Point:(IP2) Figure shows both Second order Input Intercept Point(IIP2) and Second Order Output Intercept point(OIP2) with slope of 2. IIP2= PIN + Po – PIMD.
What is 3rd order intermodulation?
3rd order intermodulation products (D3 and D4) are the result of nonlinear behavior of an amplifier. The input power level into the amplifier is increased by 1 dB in each successive frame.
What is output P1dB?
As is well known, the 1dB compression point, or P1dB, is the power level where the output power of a device, such as an amplifier, starts to drop off from the linear input/output power curve, and reaches a point where the actual output power is 1 dB less than the theoretical linear curve.
How is IP3 output calculated?
IP3 can be determined by applying 2 equal power monotones and measuring a fundamental power and a 3rd order power (either 2f2-f1 or 2f1-f2) at the output. Then apply these measured values to Equation 4.
What is IP2 in amplifier?
The Second Order Intercept Point, also known as the SOI, IP2, or IIP2 (Input Intercept Point), is a measure of linearity that quantifies the second-order distortion generated by nonlinear systems and devices. Examples of frequently used devices that are concerned with this measure are amplifiers and mixers.
What is a 3rd order intercept point?
Third-order intercept point. In telecommunications, a third-order intercept point (IP 3) is a specific figure of merit associated with the more general Third Order Intermodulation (TOI) distortion, which is a measure for weakly nonlinear systems and devices, for example receivers, linear amplifiers and mixers.
How is the third order intercept point of a superheterodyne receiver determined?
Determination of a third-order intercept point of a superheterodyne receiver is accomplished by using two test frequencies that fall within the first intermediate frequency mixer passband. Usually, the test frequencies are about 20–30 kHz apart.
What is the difference between input and output intercept point?
Input and output intercept point differ by the small-signal gain of the device. 3rd order intermodulation products (D3 and D4) are the result of nonlinear behavior of an amplifier. The input power level into the amplifier is increased by 1 dB in each successive frame.
What is an intercept point?
The intercept point is a purely mathematical concept and does not correspond to a practically occurring physical power level. In many cases, it lies far beyond the damage threshold of the device. Two different definitions for intercept points are in use: Based on harmonics: The device is tested using a single input tone.