Is insertion loss Same as return loss?

The ratio of incident power to transmitted power, in dB terminology, is the insertion loss. The ratio of incident power to the reflected power, in dB terminology, is the return loss.

Which instrument gives more accurate insertion loss?

OLTS
An OLTS provides the most accurate insertion loss measurement on a link by using a light source on one end and a power meter at the other to measure exactly how much light is coming out at the opposite end.

What is return loss in coax cable?

Return loss is a measure of VSWR (Voltage Standing Wave Ratio), expressed in decibels (db). The return-loss is caused due to impedance mismatch between two or more circuits. For a simple cable assembly, there will be a mismatch where the connector is mated with the cable.

Is higher insertion loss better?

Insertion loss is expressed in decibels, or dBs, and should be a positive number as it indicates how much signal was lost by comparing input power to output power. The lower the number, the better the insertion loss performance – an insertion loss of 0.2dB is better than 0.4dB.

How do you fix insertion loss?

Fixing links that have failed insertion loss normally involves reducing the length of the cabling by removing any slack in the cable run. Excessive insertion loss can also be caused by poorly terminated connectors / plugs. A poor connection can add significant insertion loss.

What is a good return loss?

While different systems have different acceptable return loss limits, 15 dB or better is a common system limit for a cable and antenna system. The return loss scale is normally set up from 0 to 60 dB with 0 being an open or a short and 60 dB would be close to a perfect match.

How do you calculate insertion loss?

Calculating Transmission Line Insertion Loss

1. Calculate the estimated worst loss of each component in the transmission line system.
2. Add all the component’s estimated worst losses together to calculate total insertion loss in the transmission line system.

What is bad VSWR?

Poor VSWR/Return. Loss can damage transmitters, reduce the coverage area, and lower data rates. For instance, a return loss of 10 dB means that 10% of the total power is not radiated and (if the transmitter is still running) that the coverage area is 10% smaller than the transmitter power settings might imply.

Why is the VSWR negative?

In this case the VSWR will be 1:1 and the voltage and the current will be constant over the whole length of the feed line. Return loss is a measure in dB of the ratio of power in the incident wave to that in the reflected wave, and we define it to have a negative value.

What causes high insertion loss?

Excessive length is the most common reason for failing insertion loss. Fixing links that have failed insertion loss normally involves reducing the length of the cabling by removing any slack in the cable run. Excessive insertion loss can also be caused by poorly terminated connectors / plugs.

Is insertion loss positive or negative?

Standard nomenclature is to express insertion loss as a negative number for attenuation and positive for gain. Insertion loss is defined in equation (2.13), where Vt is the voltage transmitted and Vr is the voltage received.