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# What is IIP2 and IIP3?

## 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. OIP2= Po – PIMD.

What is IIP2?

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.

### Why is IP2 important?

The second order intercept point (IP2) of a direct conversion receiver system is a critical performance parameter. It is a measure of second order non-linearity and helps quantify the receiver’s susceptibility to single- and 2-tone interfering signals.

What is OP1dB?

An important gain compression parameter is the OP1dB which is the power input that results in a 1 dB compression of the output power (OP). For this example, the OP1dB is approximately 2 Watts because at that input power level, the green curve is at 6 Watts and the red curve is at approximately 5 Watts.

#### What is P1dB and IP3?

A common rule of thumb for the relationship between the 3rd-order intercept point (IP3) and the 1 dB compression point (P1dB) is 10 to 12 dB. For instance, if a fixed level of 12 dB below IP3 is used and the IP3 for the device is +30 dBm, then the P1dB would be +18 dBm.

How is IP2 calculated?

IP2 is calculated based on the power of the single applied tone (even though this is all the power applied to the system, unlike what is done in the two-tone calculation), and on the DC output power (where the other, higher frequency product, which is at 2f1 , is ignored).

## What is RF IMD?

Intermodulation Distortion (IMD) occurs when two or more signals are used in a non-linear system. The products 2f1 and 2f2 are known as “Harmonics” which are nothing but replicas of a signal appearing at integer multiples of the fundamental signal. These sideband frequencies are considered to be undesirable.

Is compression a gain?

The makeup gain of a compressor is the gain applied to the signal after the compression takes place. Makeup gain is typically used to bring the peaks of the compressed signal up to the same level as the peaks pre-compression, thereby maintaining the same peak level while raising the overall level.

### What is P1dB and P3dB?

Output power is defined in terms of the 1 dB compression point (P1dB) and P3dB (peak output power), which is usually very close to the saturated output power capability of the amplifier. P1dB is the peak output power at which the original input signal is compressed 1dB. P3dB is the peak output power at which the…

What is the power of the input signal at the IIP2 power level?

At the IIP2 power level, the total input signal power isdefined as equal to the total power in the output IM2products (equation 4) after being referred to the input.This is done through dividing by the gain factor, |a1|2. As aresult, we can write that: 2A4 2/R = 2 2IIP2IIP2×a× ⇒(Eq 5)

#### What is the coefficient of IP2?

The coefficient a 2 is equal to where IP2 is the single tone intercept point in watts. Note that the 2-tone IP2 is 6dB below the single-tone IP2. The more linear the element, the smaller a 2 is. Every signal entering the nonlinear element generates a signal centered at zero frequency.

What is the power level of the IM2 products?

Based on a total two-tone input power equal to P2T=A2/R, the total power level of the IM2 products (equation 4) referred to the receiver input can be expressed as: IM2 = 2 ×P2 2T2 a 2A4

## What is IP2 (2nd order intercept point)?

The second order intercept point (IP2) of a direct conversion receiver system is a critical performance parameter. It is a measure of second order non-linearity and helps quantify the receiver’s susceptibility to single- and 2-tone interfering signals.