Effects of IP Transport Compression on a Broadcast FM MPX Signal

The use of IP transport for FM composite (MPX) signals is increasing in the US and elsewhere. To reduce network bandwidth requirements, manufacturers have implemented several types of data compression for use in MPXoIP transport.  This presentation will showcase actual performance measurements in a side-by-side comparison of the leading products from manufacturers such as Omnia, APT, GatesAir, 2WCom and Digigram.  The primary focus is on audio performance – frequency response, stereo separation, THD. Various bit rates are tested, including 16 bit linear, and compared to a reference configuration with no IP transport at all.  We will also examine if the various compression solutions have any measurable effect on the Nielsen PPM signals embedded in the audio.