Applications

• Implementation Margin of a Satellite Communication System

  The Implementation Margin of a satellite communication system is defined as the degradation of the signal after travelling through the up and downlink equipment. In order to find this, an EbNo generator such as the Noisecom CNG-EbNo Series can first be used to carry out an IF loopback test of the modem in order to find bit error rate (BER) values at different Eb/No ratios. A plot of these values can then be compared with the theoretical curve for the digital modulation scheme being used. The resultant difference is termed the implementation loss of the modem, and this value is used as a reference level for the second part of the test, in which the implementation margin of the complete up and downlink is found.

• Adding Analog Noises to the DOCSIS 3.0 Cable Network

  Injecting Additive White Gaussian Noise (Gaussian Noise) of varying power from Noisecom noise generators into the cable network is an effective way to assess the extent of cable network’s ability to cope with Gaussian Noise interferences of varying intensity. In this application note, we highlight area where Gaussian Noise should be added to examine its impact and uses some of the signal quality metrics to assess the health of the DOCSIS network.

• Calculating the Max Eb/No Ratio You Can Provide with a Noisecom CNG-EbNo Unit

  Eb/No is a very important parameter for those who work with digital communication systems. Usually this term shows up while discussing bit error rate (BER) or modulation methods in a communication system.

• Noise Basics

  What Is Noise? All materials produce noise at a power level proportional to the physical temperature of the material. Chinese application note available.

• Noise by the Numbers

  Learn all you need to know about what noise can do, how it is created, types of noise Noisecom provides and how to control it. It is a great resource to define your noise requirements and identify what Noisecom product or products you can use: component, module or instrument. Chinese application note available.

• Measuring Crest Factor

  This document provides Noisecom's method of measuring crest factor of a noise source using a LeCroy Wavepro 7200 Oscilloscope. Chinese application note available.

• Accurate Es/No for DOCSIS / CATV BER Measurements

  The Data-Over-Cable Service Radio Frequency Interface Specifications call out BER performance vs. Es/No as required tests for both the Upstream CMTS (Cable Modem Termination System) and Downstream CM (Cable Modem) receivers. Chinese application note available.