33
Sabine 2.4 GHz Smart Spectrum
®
Wireless
LIT-SWM7000-OG-EN-070615.pmd - rr
© 2007 Sabine, Inc.
11. MULTIPLE SYSTEMS OPERATION
11.1. Overview
In many circumstances a single wireless microphone system is all that will be
in use at any one time. Larger applications (church, concert hall, theater
stage, conference room, etc), however, can often require a large array of wire-
less microphones, all demanding flawless uninterrupted simultaneous op-
eration.
Multiple system operation presents at least two important operational chal-
lenges: interference among transmission channels, and setup complexity.
The Sabine SWM7000 provides powerful solutions to both, particularly the
interference problems associated with two or more RF channels at work at the
same time, at the same location.
11.1.1. Multiple System Interference
Sabine’s SWM7000 addresses multiple system interference with two strat-
egies. First, greater available bandwidth in the 2.4-2.4835 GHz range means
more channels can occupy the band, i.e., the expanded range can be divided
into a greater number of separate transmission/reception bands. Second,
with Smart Spectrum transmission and reception, channels are more toler-
ant of interference. The net result is that the SWM7000 offers the potential for
many more simultaneous transmission channels than conventional UHF or
VHF systems.
While such performance benefits are one of the major advantages of the
SWM7000, more systems working at the same time leads to a greater po-
tential for complexity. Fortunately, the SWM7000 also offers tools to simplify
setup and operation.
11.1.2. Setup Complexity
Multiple wireless systems in a large installation are of course more compli-
cated than a single transmitter/receiver. More space is needed, and the
sheer quantity of transmitters and receivers that may be in use at a single
installation can prove difficult to manage. The SWM7000 series helps man-
age such potential complexity with four strategies and/or system accesso-
ries:
1.
First, the SW72 and SW72-NDR receivers offer a 50% space-saving
advantage with 2-channel receivers that occupy the same 1U space as
single channel receivers. Each channel in a 2-channel system shares
the true diversity operation of the two antennas connected to the single
receiver chassis.
2.
Second, the optional SWA6SS (six-system antenna distribution ampli-
fier) greatly reduces the complexities of multiple receiver antenna de-
ployment. Since each receiver has two (diversity) antennas, which can
be mounted on either the rear or front panel, multiple receivers at one
location can potentially create a forest of antennas protruding from the
front or back of a rack. The SWA6SS Antenna Distributor reduces the
number of antennas to as few as 1/6 what would otherwise be needed.
An added important advantage of using the SWA6SS is its distributed
signal boost provided to all the antenna outputs, delivered while main-
taining diversity in all attached reception channels.
3.
Third, large installations often entail long distances from transmitters
to receivers, or the presence of obstacles (walls, for example) in the
transmission path that can interfere with clear reception. While the
SWM7000 series is designed to minimize these kinds of problems
without accessories, the SWASS-EXT-2 (set of two extension antennas,
shown in figure 12b on page 36) may prove helpful or even necessary
in some situations. In addition to providing remote and/or desirable
low profile positioning with improved reception, the SWASS-EXT-2 also
adds another 18 dB of antenna gain for even more reliable system
performance. The Extension Antenna and Distribution Amplifier com-
ponents are also designed to operate in tandem, with the Extension
Antenna plugged directly into the amp, which can then feed (via cable)
Multiple Systems Operation
