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Maintains Protection after Initial Strike or Pulse
M/A-COM offers a complete series of RF Coaxial Lightning &
EMP Protection Devices for use in cellular infrastructure appli-
cations. EMP (electro-magnetic pulse) occurs primarily as a
result of direct lightning strikes to infrastructure equipment
which can produce fast rising electric fields within micro
seconds. These electric fields induce high voltage pulses
through unprotected antennas and coaxial transmission
cables which can ultimately lead directly to the primary com-
munication equipment. The EMP threat, generated from un-
predictable lightning strikes is a serious concern for cellular
operators around the world. Damage from a lightning strike
can result in costly repair of equipment as well as significant
loss of airtime service to subscribers.
M/A-COM RF coaxial lightning protection (LP) devices have
been designed for use in commonly deployed cellular
infrastructure including GSM, NAMPS, PCS 1900 and
DCS 1800 operating formats. The use of coaxial lightning
protection has two primary benefits for cellular applications.
First, RF coaxial lightning protection can easily be inserted
into existing infrastructure architecture either as a cable
assembly or as an in-line adapter. This facilitates cell site
design and retrofit capabilities. Secondly, the RF coaxial
protection has been designed to facilitate and not degrade
RF performance during normal operation of the system.
/4 Stub Tuners
/4 stub tuners are three port coaxial devices. The third port,
extending from the main electrical path, serves as a
terminated short circuit element at a predetermined distance
from the RF transmission path. This distance is designed to
be exactly one quarter wavelength at the desired centering
frequency (Fo). /4 stub tuners offer very low VSWR and
feature very high attenuation of incoming pulses but must be
applied across relatively narrow bandwidths (鹵 70 MHz).
M/A-COM offers standard designs for the most popular
cellular frequency bands to facilitate usage without the need
for a custom design. Stub tuners offer the greatest protection
for sensitive electronic components as they have neither the
sparkover or residual voltage characteristics of GDT devices.
Stub tuners are extremely reliable and maintenance free
since they incorporate no active components. Standard stub
tuner designs exist for GSM, PCS 1900 and DCS 1800
frequencies with a wide variety of connector interfaces such
as Type N and 7-16 available. Cable assemblies, including
low loss cable options, are also available to provide complete
in-line solutions for base station design.
Call your local M/A-COM sales office or global Applications
Engineering group for more information on our RF coaxial
lightning protection. M/A-COM is an ISO-9001 globally
certified manufacturer.
Surge Protectors
These devices incorporate internal gas discharge tube (GDT)
technology to provide a low impedance path to discharge the
EMP to ground. The GDT is hermetically sealed with an inert
gas which is not radioactive and requires no special handling.
GDT devices are broadband due to their inherently small
capacitance and cover frequencies up to 2.5 GHz. Once a
GDT device has been activated with an impulse and the
voltage level dissipated, the device becomes inactive and will
require subsequent maintenance or replacement. Surge
protectors are available in convenient bulkhead mounting
configurations with a wide variety of standard interface
choices including Type N, 7-16 and SMA.
Specifications Subject to Change Without Notice.
M/A-COM, Inc.
North America:
Tel. (800) 366-2266
Fax (800) 618-8883
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Asia/Pacific: Tel. +85 2 2111 8088
Fax +85 2 2111 8087
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Europe: Tel. +44 (1344) 869 595
Fax +44 (1344) 300 020
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