MobileMapper™ Beacon USER MANUAL www.thalesgroup.
Copyright Notice © 2005 Thales S.A. All rights reserved. No part of this publication or the computer programs described in it may be reproduced, translated, stored in a retrieval system, or transmitted in any form or by any means, electronic, mechanical photocopying, recording, or otherwise, without prior written permission of Thales Navigation.
Table of Contents Preface..........................................................................................................1 Key Features.........................................................................................2 Introduction.................................................................................................3 Receiving Your Shipment ....................................................................3 MobileMapper Beacon System ...........................................
Preface Welcome to the Thales MobileMapper™ Beacon User Manual and thank you for buying this high-performance, beltmounted DGPS system. This product is an accessory to the MobileMapper and MobileMapper CE handheld GPS/GIS data collection systems. The purpose of the MobileMapper Beacon system is to receive accuracy-enhancing corrections from Coast Guard beacon networks.
The MobileMapper Beacon may also be used with 3rd-party GPS systems that accept RTCM SC-104 corrections via a Bluetooth or traditional hard-wired serial connection. The following figure shows the MobileMapper Beacon system. We have written this document to assist you with learning how to use the MobileMapper Beacon system, how it operates with GPS equipment, and provide some general information on Coast Guard beacon technology.
Introduction Note - Though the MobileMapper Beacon is primarily intended for use with our MobileMapper and MobileMapper CE GPS/ GIS data collections systems, it may be used with any GPS system that support RTCM-based real-time differential corrections. In order to connect to other devices, you will need to ensure the GPS supports either Bluetooth wireless technology or an RS-232 serial port. The Thales MobileMapper Beacon system is an accessory to the Thales MobileMapper CE GPS data collection system.
Using the MobileMapper Beacon User Interface The MobileMapper Beacon user interface is located on the top of the unit. This interface consists of a power button and three lights. A red light next to the power button indicates the unit is on. A green light comes on once the unit has locked onto a DGPS transmitter with a signal-to-noise ratio greater than seven and is sending the corrections to the GPS receiver.
The following table provides detail regarding the status lights. LED Color Function Power indicator - when the MobileMapper Beacon is powered, this LED will solidly illuminate. Note: This LED does not have a Red label, but is connected to the Power Button to indicate what it is for. Bluetooth indicator - this LED will illuminate when there is a Bluetooth connection between the MobileMapper Beacon and Blue a Bluetooth compatible device and off when there is no Bluetooth connection.
The easiest way to insert batteries into a clip is by sliding them up from under the clip. There are some moulded stops designed for the proper alignment of the batteries in the clip. This ensures that the battery terminals make the proper contact when the compartment door is fastened to the unit. It is important to insert the batteries into the clip with alternating polarity. A fully loaded clip is shown below.
It is not necessary to remove the MobileMapper Beacon from the belt-mounted carrying system in order to open the battery compartment. Just unscrew the knurled silver knob until you feel the compartment door come loose and pull the door away from the unit. You will find that the fastener disengages and 'pops' toward you. You can then use the fastener to open the door.
To secure the battery compartment door, slide it into place. Now gently push the door down until the gasket engages. Pressing the door down, screw the knurled knob into the unit assuring a good seal. Warning - Please use only batteries of the same type. Do not mix alkaline batteries with 1.5-V Lithium or NiMH batteries. Please do not mix batteries of different charge levels. This can cause the batteries to fail, causing damage to you or the MobileMapper Beacon.
Powering the MobileMapper Beacon To turn on the MobileMapper Beacon, press the black, recessed power button on the top of the unit as seen in the photographs below. When powered, the red LED light turns on. When the MobileMapper Beacon is turned off, it still draws a small amount of current from the batteries. If you will not use the receiver for a number of weeks, you may wish to remove the batteries so they do not lose their charge.
Belt-mounting The MobileMapper Beacon is designed to mount easily onto a belt using the included carrying system. You may alternatively carry the Beacon in a backpack or mount it on a range pole in some fashion. Wherever you carry the MobileMapper Beacon, please be sure to separate it from your GPS receiver or any other electronic device (cell phone, PDA, etc.) by at least 75 centimeters (30 inches) to prevent radio interference.
Bluetooth Wireless Communications with MobileMapper CE You can also use a serial data cable to communicate with the MobileMapper CE. The original (non-CE) MobileMapper receiver is not Bluetoothenabled, and so you must use a cable link. This is available as an option. The MobileMapper Beacon's primary method of communicating coast guard beacon corrections to the MobileMapper CE system is via an internal Bluetooth wireless communications module.
Establishing a Bluetooth Connection For details regarding the process of connecting to the MobileMapper Beacon system with the MobileMapper CE, consult the section below, "MobileMapper CE Bluetooth Manager." When the MobileMapper CE has established a Bluetooth connection to the MobileMapper Beacon system, a blue LED will illuminate on the top of the MobileMapper Beacon. This blue LED is identified with the Bluetooth logo as shown in the following figure.
Serial Communications The second method of communicating with the MobileMapper Beacon is through a traditional RS-232 serial port. When using a serial cable, you will not see the Bluetooth light illuminate; however, serial data will be downloading into the GPS system. A PC-interface cable is supplied with the MobileMapper Beacon system for serial communications.
To remove the cable, squeeze the tabs on either side of the cable and gently pull it out. In the event that you are connecting the MobileMapper Beacon to a non-Thales-branded GPS receiver, you may need to plug a gender changer and null modem adapter into the DB9 end of the Beacon's serial cable. Using the optional serial cable (P/N 980816), it is easy to connect Thales MobileMapper to MobileMapper Beacon.
Beacon Lock When a signal from a coast guard beacon station has been acquired, the green lock indicator light will illuminate as shown below. If you are operating in a weak signal environment, or with sufficient environmental noise to cause interference with the signal, this light will either be intermittently illuminated or may not come on at all.
MobileMapper CE Bluetooth Manager In order to use corrections from the MobileMapper Beacon, the MobileMapper CE's Bluetooth Manager must first be used to discover the Beacon product, and then establish a connection. To access the Bluetooth Manager: • Tap the Windows butterfly icon in the lower left of the MobileMapper CE screen with the stylus. • Then access Settings>Control Panel>BTManager. The Bluetooth icon will appear in the system tray.
Windows CE Configuration Utility A standalone MobileMapper Beacon Configuration Utility is also available at ftp.thalesnavigation.com. This tool allows you to tune the receiver and monitor the reception in Windows XP/2000 or Windows Mobile 2003 environment. As part of our MobileMapper CE GPS Utilities, we have a utility that allows you to modify the correction source used by the GPS. Within this interface, you will also have access to communicate with the MobileMapper Beacon system.
Tuning the Beacon Frequency There are two methods that you can use to tune the beacon receiver inside the MobileMapper Beacon. The first method is the default mode, which is automatic operation. The second mode is manual operation where you specify the frequency to which you want the receiver to tune. We recommend that you use automatic tuning when operating in an area where you are unsure of the stations available or their frequency details.
You will see that you're free to either tune by the frequency and MSK (data) rate of the station, or by station name, chosen by region, country, and beacon name. The following window displays the content of the 'Status' tab. You will see in this window the current tuning settings, including the station name, frequency, but rate, and station ID. Below this information is the lock condition, signal strength (SS) measured in dBµV, and signal to noise ratio (SNR) measured in dB.
Monitoring Reception Performance Beacon reception performance is described by a signal to noise ratio (SNR) number. Essentially what this number indicates is how much the signal 'peaks' above the noise floor. A taller signal would mean better reception performance than a shorter signal above the noise floor. The SNR is measured in decibels (dB). The following table describes reception performance based on the SNR indicator.
To ensure that you provide the MobileMapper Beacon with the best chance to receive a relatively noise-free signal, here are some precautions that you should be aware of: • If you use a belt-worn pager or mobile phone, ensure that you wear it on the opposite side of your body so that it's away from the MobileMapper Beacon. • Wear the MobileMapper Beacon on the same side of your body as write with a pen. For instance, if you are right-handed, wear the beacon system on your right hip.
Note - If you see '-100' at any point in the SNR or SS fields, this just means that the receiver is changing frequency or data rate of the signal automatically. This will not happen in when the system has been tuned in manual mode by selecting the frequency or station name. 22 If you are able to communicate with the receiver with the Configuration Utility, you know the receiver is functioning in some capacity. The next step is to monitor the signal strength.
Coast Guard DGPS Service The MobileMapper Beacon receives differential correction data transmitted by coast guard stations located in many regions throughout the world. This chapter aims to provide you with practical knowledge of this coast guard service, to empower your use of this product.
The portion of the beacon signal broadcast skywards is known as the sky wave. Depending on its reflectance, the sky wave may bounce off the ionosphere and back to Earth causing reception of the ground wave to fade. Fading occurs when the ground and sky waves interfere with each other. The effect of fading is that reception may fade in and out. However, this problem usually occurs in the evening when the ionosphere becomes more reflective and usually on the edge of coverage areas.
Spatial Decorrelation Note - Due to effects of spatial decorrelation, we recommend that you consistently use a specific beacon station as much as possible. If, for some reason this station is not available, you will need to determine if a secondary station is available. Depending on the range from yourself to the beacon, the environmental conditions may differ between the base station site and your location.
• The low frequency has benefit in penetrating tree-cover, but it is also susceptible to man-made sources of noise from various electronics or electrically driven equipment. This susceptibility shows up in reduced SNR, which could lead to less reliable reception. • ·Local Area Service - beacon is a local area service where only one station is providing correction data to the user-base. This is a strength such that it provides good quality corrections when near the beacon site.
This could result in a similar error as spatial decorrelation in Coast Guard beacon, however, this is likely to be less significant. More significant is that the ionospheric map is downloaded to users only every 5 minutes. Recent past has shown that the ionosphere, during peak solar activity, can change more quickly than this update rate, causing a significant source of error. This is a very rare condition. Solar activity can be monitored by consulting various Web sites, such as www.spaceweather.
- The Type 7 message contains the radiobeacon almanac information composed of location, frequency, service range, and health information of sister stations for the currently tuned beacon. - The Type 16 message provides users with a 90 character text string that may contain information regarding the status of the system, weather warnings, etc. Radiobeacon DGPS is often referred to as a local-area service, as the data broadcast is appropriate for use within the coverage range of the station.
MOBILEMAPPER BEACON USER MANUAL Thales Mobile Mapping Solutions Contact Information In USA +1 909 394 5000 • Fax +1 909 394 7050 Toll Free (Sales in USA/Canada) 1 800 922 2401 In South America +56 2 273 3214 • Fax +56 2 273 3187 Email mobilemapping@thalesnavigation.com In Singapore +65 6235 3678 • Fax +65 6235 4869 In China +86 10 6566 9866 • Fax +86 10 6566 0246 Email mobilemappingapac@thalesnavigation.
