User's Manual

Electrostatic Discharge (ESD) Nexus FT

iv 044-05251 Rev C

Human Exposure to RF Radiation

Safe distances must be kept when working around antennas. The following paragraphs describe the cautions

to be aware of during the installation and maintenance of antenna systems and how to calculate safety

distances needed for RF radiation at different antenna power and frequencies.

Antennas

To be able to receive and transmit signals, a Nexus FT is connected

to a donor antenna directed towards the

base station and a service antenna directed towards the coverage area. A fiber optic cable from the base

station might, however, be substituted for the donor antenna.

Installation and Maintenance of Antenna Systems

Installation and maintenance of all antenna systems must be performed with respect to the radiation exposure

limits for p

ublic areas. The antenna radiation level is affected by Nexus FT output power, antenna gain, and

transmission devices such as cables, connectors, splitters and feeders. Also have in mind the system minimum

coupling loss, typically between 25dB and 35dB, is determined by a standard with the purpose to protect base

stations from noise and other performance dropping effects.

Radiation Exposure

The World Health Organization (WHO) and International Commission on Non-Ionising Radiation Protection

(ICNIRP) ha

ve determin

ed recommendations for radiation exposure. ICNIRP recommends not to exceed the

following radiation power for public exposure:

Frequency Radiation power

800/900 MHz 4.5W/m²

1800/1900 MHz 9.0W/m²

2100 MHz 10.0W/m²

For antennas larger than 20cm the maximum radiation po

wer ca

n be calculated by using the following formula:

Electrostatic Discharge (ESD)

ESD can severly damage essential parts of the equipment if not handled carefully. Parts on

printed circuit board assemblies (PCBA) as well as other parts in the equipment are sensitive

to ESD. Never touch the PCBA or uninsulated conductor surfaces unless absolutely

necessary.

If you must handle the PCBAs or uninsulated conductor

surfaces, use ESD protective

equipment or first touch the chassis with your hand. Never let your clothes touch PCBAs or

uninsulated conductor surfaces and always store PCBAs in ESD-safe bags.

S= P/(4

πr

)

S = Radiation power in W/m²

P = Output power in W

r = Distance between antenna and human in meters