AnyTone AT-7100 Посібник користувача - Сторінка 16
Переглянути онлайн або завантажити pdf Посібник користувача для Ретранслятор AnyTone AT-7100. AnyTone AT-7100 20 сторінок. Gsm+dcs+3g/umts/wcdma tri-band mini repeaters
Друкувати сторінкуd. To prevent affecting signal coverage range caused by oxygenation resulting from
moisture, all joints should be sealed by water-resistant adhesive tape, avoiding
water leakage into mini repeater through cable causing short-circuit.
FREQUENTLY ASKED QUESTIONS
Tri- band mini repeater system self-excitation
a.The reason of Self-excitation phenomena: the isolation degree of antenna is not
enough (indicator light shows in "orange")
b.There are two methods to overcome the self-excitation phenomena. One is to
enlarge the isolation degree between donor and service antenna; the other is to
reduce mini repeater's gain. When the desired coverage area is smaller, your can
just use the second method.
When the desired coverage area is larger, you should adopt the frist method. It
mainly adopts the following methods to enlarge isolation degree in project:
1) Enlarge the horizontal and vertical distance between donor and service
antennas.
2) Add barriers, such as shielding net.
3) Enhance the direction of donor antenna, such as paraboloid antenna.
4)Utilize landform and building to enhance isolation degree.
In addition,device trouble and poor contact of cable joints,which cause high VSWR,it
also will cause self-excitation. But generally situation occurs barely. In the installation
project, self-excitation is mainly caused by small isolation degree of antenna and
feeding system.
The simple way to judge whether the device has self-excitation: Connect dummy
load to MS or BS port of repeater, when the power indicator light is on, you can
judge that the device itself exists self-excitation.
Frequent soft handoff (namely ping-pong phenomenon)
It mainly indicates that in the mini repeater coverage area,mobile phone users have
been switched repeatedly among two or more pilot frequencies of base station,and
usually connect into many base stations at the same time. The reason is the mini
repeater antennas are installed improperly; donor antenna has been installed in the
area where the coverage of base stations overlaps, and receives pilot frequency
signals from many base stations,the signals have similar intensity and alternately
USER'S MANUAL OF MINI REPEATER
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