GLX-D Modulation and Transmission Scheme

Date Updated: March 30, 2015 FAQ #4635
What is the modulation and transmission methods used by GLX-D?

Shure has spent years developing and optimizing proprietary modulation schemes. Shure does not use an “off the shelf” modulation or transmission scheme, but a digital design that’s unique and proprietary to Shure.
GLX-D modulation is a proprietary version of Frequency-Shift Keying (FSK).
GLX-D transmits via Frequency hopping where it hops among 3 active signals, and has 3 backups to choose from if needed.
The sampling rate is 44.1 kHz. Extensive listening tests determined that there was no discernable audible difference between 44.1 kHz and 48 kHz sampling rates.  By using 44.1 kHz instead of 48 kHz, the "saved" data bits are used to improve RF reliability.
Additional information on GLX-D operational concepts is considered confidential intellectual property.