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Testingcellularnetworkinfrastructure
often requires measurement and
data collection from dozens – even
hundreds – of base stations (BTS)
within a test environment. The
volume and complexity of signal
traffic in these multi-device, multi-
user test systems necessitates
commensurate capability for routing
signals between base stations
and test stations. By partnering
with customers to lower costs and
improve efficiency in high-volume
test systems, Mini-Circuits has
developed a line of high-order switch
matrices supporting a wide variety of
switching configurations and control
methods. This article will present a
case study of a 20 x 6 non-blocking,
full access switch matrix used to
facilitate signal routing in a cellular
network test system with extensions
for other applications.
Case Study: A High Order Switching
System for Cellular Network Testing
A cellular network operator was
building a test setup to validate new
BTS equipment on their network. The
test system needed to evaluate each
channel of new BTS nodes to verify
they were meeting specifications;
it needed to confirm that new
equipment
worked
alongside
existing, heterogeneous equipment
without adverse interactions; and
it needed to allow validation of
supported handsets with the new
BTS equipment.
For this functionality, the customer
required a signal routing system to
connect 6 independent test stations
to any or all of 20 base station
(BTS) channels. The setup needed
to allow multiple users to connect
to the same BTS if necessary, but
also required a control mechanism
to limit which test stations could
access which BTS. To satisfy
these requirements, Mini-Circuits
developed the ZT-20X6NB, a 20 x
6 non-blocking full access switch
matrix. This bi-directional switch
matrix covers the key worldwide
telecommunications bands from 600
MHz to 6 GHz and can be programed
to connect ports B1 – B6 (shown in
Figure 1) to any combination of ports
A1 – A20, such that multiple input
ports may be routed to the same
output port simultaneously. Because
of its flexibility, this non-blocking
configuration is ideal for multi-user,
multi-device test systems of the kind
High-Order Switch Matrices
Facilitate Network Infrastructure Testing
Chi Man Shum, Mini-Circuits
26 l New-Tech Magazine Europe