User's Manual

Axell BSF3604-490-510-DP-AC (61-103001) Repeater

Product Description and User’s Manual

1.4.4 Antenna Installation

Installation of an antenna must comply with the FCC RF exposure requirements. The antenna

used for this transmitter must be mounted on permanent structures.

The FCC regulations mandate that the ERP of type B signal boosters should not exceed 5W, this

is equivalent to 8.2W EIRP.

Therefore the max antenna gain allowed for this type of signal booster should be limited to the

values given by equation 1 (below) for the service antenna.

Equation (1) - Max SERVICE antenna gain

Max SERVICE antenna gain (dBi) = 39.1 – (37dBm - # of antennas in dB – cable losses in dB).

For example:

No. of Antennas Cable Losses Max Allowed Antenna Gain

4 3 39.1 - (37-6-3) =11.1dBi

1 3 39.1- (37-0-3) = 5.1dbi

10 3 39.1- (37-10-3) = 15.1dbi

1.4.5 Compliance with FCC deployment rule regarding the radiation of noise

and intermodulation product

Good engineering practice must be used in regard to the signal booster’s radiation of

intermodulation products and noise. Thus, the gain of the signal booster should be set so that the

ERP of the output of intermodulation products from the signal booster should not exceed the level

of -30 dBm in 10 kHz measurement bandwidth and noise from the signal booster should not

exceed the level of -43 dBm in 10 kHz measurement bandwidth.

In the event that the intermodulation or noise level measured exceeds the aforementioned values,

the signal booster gain should be decreased accordingly.

In general, the ERP of noise on a spectrum more than 1 MHz outside of the pass band should not

exceed -70 dBm in a 10 kHz measurement bandwidth.

The BSF-3604 61-103001 Repeater has a noise level of -64 dBm in 10 kHz measurement at 1

MHz spectrum outside the passband of the signal booster, worst case intermodulation products at

around -15 dBm in a 10 kHz bandwidth and an in-band noise level at around -37 dBm in a 10 kHz

bandwidth. Therefore, the noise or intermodulation product at the antenna input port should be

calculated based on equation (2).

Equation (2) - Input Noise or intermodulation product to service antenna

Input Noise to service antenna:

-XX dBm + Service Antenna gain – Antenna splitter losses in dB – cable loss in dB

Example: Intermodulation product

Signal booster connected to 10 service antennas with a 100m long ½ inch cable.

Losses of such a cable with the connectors = ~ 12dB

Assuming 10 service antennas: antenna splitter losses = 11 dB

Based on equation (2) Input antenna noise (to the antenna) = -15-12 -11= -38 dBm ERP

The intermodulation product to the antenna should be -15 -12-11= -38dbm ERP