Broadband Noise for Carrier to Noise Ratio (C/N) Generation

Abstract

Noisecom CNG-EBNO creates accurate Carrier to Noise Ratios (C/N) or Bit Energy to Noise Density Ratio (Eb/No). The instrument takes user entered parameters and via an internal automated process creates the desired C/N ratio at the output of the instrument.

Test your System's Immunity to Broadband Noise

Noisecom CNG-EBNO with Spectrum Analyzer (Discussion)

Product:
Noisecom CNG-EBNO creates accurate Carrier to Noise Ratios (C/N) or Bit Energy to Noise Density Ratio (Eb/No). The instrument takes user entered parameters and via an internal automated process creates the desired C/N ratio at the output of the instrument.

Problem:
Our customer has anIF Band (data stream) with a number oftelemetry channels (carriers) in the frequency band of interest. The customer wants to create an accurate Carrier to Noise Ratio (C/N) on a specific carrier frequency within that data stream.

Traditional approaches:
Traditional CNG-EBNO units do not have the ability to be frequency selective within an IF Band with multiple carriers. This is due to the fact a broadband power meter is used internal to the instrument which takes an average power of all of the carriers at the input to the instrument. The C/N Ratio is then calculated for the average power of all the carriers.

Solution:
Replacing the broadband power meter with an embedded spectrum analyzer, we are able to characterize and isolate the input data stream. This will allow us to accurately measure the power of the carrier frequency of interestwhich isthen used to generate the C/N ratio of the signal.


Figure 1: Input Data Stream to CNG-EBNO


Figure 2: Output of CNG-EBNO using a User Specified carrier as the reference.

Significant Features of CNG-EBNO series:

• Custom broadband noise frequenciesup to 40 GHz
• Output power +5dBm.
• Manually controlled by a front panel touch screen display.
• Remotely controlled via Ethernet, GPIB or RS232/RS422/RS423.
• 0.1 dB step attenuator.
• 75 ohm or 50 ohm input/output impedance.
• Switchable filters for custom tailored noise bands.
• Front or rear panel input and output connectors. SMA, BNC or N types.
• Removable harddrive (military/defense applications).

If there are additional requirements for your noise application, please contact the factory for more information about custom designs.

More Resources:
Visit Noisecom official website www.noisecom.com for more information on Noisecom products.