Operating Manual

Chapter3 Installation 3

3. Installation

3.0 Overview

The pDDL2450 complies with FCC part 15 at the modular level for

operation in the license-free 2400-2483.5 MHz ISM band. This chapter

provides guidelines for installing and deploying equipment which

incorporates the pDDL2450 module.

3.1 Estimating the Gain Margin

Successful communication between pDDL2450 modules is dependent on

three main factors:

 System Gain

 Path Loss

 Interference

System gain is a calculation in dB describing the performance to be

expected between a transmitter-receiver pair. The number can be calculated

based on knowledge of the equipment being deployed. The following four

factors make up a system gain calculation:

1. Transmitter power (user selectable)

2. Transmitter gain (transmitting antenna gain minus cabling loss between

the transmitting antenna and the pDDL2450 module)

3. Receiver gain (Receiving antenna gain minus cabling loss between the

receiving antenna and the module)

4. Receiver sensitivity (Specified as -108dBm on the pDDL2450 module)

In the following illustration, the transmitting antenna has a gain of 6 dB,

and the receiving antenna has a gain of 3 dB. The cable loss between the

module and the antenna is 2 dB on both the transmitting and receiving side.

Transmitter

30 dBm

Output Power

Receiver

Sensitivity =

-105 dBm

Cable Loss = 2 dB

Antenna Gain = 6 dB

Antenna Gain = 3 dB