APN-13-8-004/A

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1. Introduction

This document details the best practice for installing the MA.203 Stingray inside a vehicle, to

preserve antenna efficiency and gain, and to reduce interference from nearby electronic

noise.

2. Antenna Placement and Cable Routing

Antennas should always be placed as far away as possible from metal and any active

electronics in the vehicle, e.g. the car’s radio system.

20cm (7.87”) is the ideal clearance and 2cm (0.78”) should be the minimum. If the antenna

is placed directly on metal, the signal cannot get through the metal to the antenna.

The RF environment of each automotive vehicle model is different so a suitable installation

point should be identified for each model of car separately. Measuring receive signal strength

(RSSI) for cellular and TTFF (Time to First Fix - Cold Start) for GPS are the most practical and

quick testing methods for installers. The device manufacturer can provide this test procedure

information.

There is a sticker on each antenna

"THIS SIDE FACES THE SKY"

showing the ideal orientation of the antenna.

The antenna should not be placed with the internal patch antenna (3M tape side) facing

downwards as it will not have a clear view of GPS satellites in the sky. The best positions are

generally facing skyward with only plastic or glass in the way. If the view above the antenna

is blocked by metal or active electronics then it may be best to place the antenna

perpendicular to the sky so it still has a direct view to some satellites. Actual best

performance can only be confirmed from testing in that location.