Overview Of Channel Coordination; Scanning Available Rf Spectrum - Shure MXW Series User Manual

Wireless Management

Overview of Channel Coordination

In North America, up to 40 Microflex Wireless channels can operate in the unlicensed 1920–1930 MHz frequency bands. In Europe, up to 80 channels can
operate simultaneously in the 1880–1900 MHz frequency range. The frequency spectrum is divided into time-slots that carry an MXW channel (audio and
control data). Channels are automatically assigned to the time-slots by the access point, which manages the spectrum and seamlessly changes slots if
interference is detected. The MXW system makes this adjustment automatically and without audio artifacts.
It is important to understand the availability of the spectrum in each environment where an MXW system will be installed or operated. An eight-channel
MXW system uses roughly 25% of the total frequency spectrum. Use the Spectrum Scan in the MXW control software to determine the maximum number of
additional channels that can be safely added to the system.

Scanning Available RF Spectrum

The MXW Wireless components operate in unlicensed spectrum that is shared with other wireless devices operating in the same area, such as cordless
phones, walkie-talkies and intercoms. The MXW control software features a scanning tool that surveys the RF spectrum for these devices. It calculates
the percentage of Radio Frequency Interference (RFI) in the area and provides recommended channel count ranges. It provides the current and peak
percentages of RFI activity for up to 24 hours.
During a scan, any microphones Linked to that Access Point are turned off in order to survey the area for interference from other devices. The scan calculates
the current spectrum and the minimum spectrum available, which provides the greatest level of safety in determining channel count availability in a space.
The Minimum Spectrum Available data will persist until a new scan is performed or the data is cleared.
Radio Frequency Interference (RFI)
The scanner analyzes the spectrum and divides the data into three
categories:
No/Low (Green): Clean RF available for MXW system.
Moderate (Yellow): Some moderate interference is detected, still usable
by the MXW system.
High (Red): Busy RF occupied by other devices.
Performing a Scan
Follow these steps to perform RF scan.
Tip: Perform the scan during typical hours of operation to best capture the
typical interference in an environment.
1. Ensure all typically used devices are turned on, including any MXW
equipment already in use.
2. Place the new MXW Access Point near the location it will be mounted.
3. Ensure the APT is on the same network and set to the same subnet as
the other MXW equipment.
4. Open the Monitor tab of the MXW control software.
5. Make sure the new Access Point is selected from the drop down on the
top left corner of the Monitor tab.
6. Press the Spectrum Scanner button. The Spectrum Scan window opens.
7. Press the Start Scan button at the top of the window. If any microphones
are Linked to that Access Point, they will be turned off.
8. Allow the scan to run for up to 24 hours. Press End Scan to end the scan
mode.
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Estimated Mic Channel Count
The scanner provides two estimate levels for MXW microphones:
Conservative (More Robust)
Reference this channel estimate for maximum channel stability. It includes
extra usable spectrum for optimal interference avoidance, allowing multiple
microphones to find available frequencies simultaneously.
Aggressive (More Channels).
Reference this channel estimate if a higher channel count is necessary for
the installation. It reserves only the minimum required extra spectrum for
interference avoidance. Be sure to occasionally monitor the spectrum and
make channel adjustments if the RFI increases.