User's Manual

ManualsBrandsTopcon America ManualsElectronicsGNSS RECEIVER SYSTEM

DRAFAFT Chapter 1

Introduction

The GRS receiver is a single-frequency, GPS+GLONASS L1 L2receiver and hand-held controller built to be the

most advanced, compact, and portable receiver for the GIS surveying market. An integrated electronic compass and

digital camera make the GRS an all-purpose, GIS field mapping unit.

The GRS receiver is a multi-function, multi-purpose receiver intended for precision markets. Precision markets

means markets for equipment, subsystems, components and software for surveying, construction, commercial

mapping, civil engineering, precision agriculture and land-based construction and agriculture machine control,

photogrammetry mapping, hydrographic and any use reasonably related to the foregoing.

The GRS provides the functionality, accuracy, availability, and integrity needed for fast and easy data collection.

Principles of Operation

Surveying with the right GPS receiver can provide users accurate and precise positioning, a requirement for any

surveying project.

This section gives an overview of existing and proposed Global Navigation Satellite Systems (GNSS) and receiver

functions to help you understand and apply basic operating principles, allowing you to get the most out of your

receiver.

GNSS Overview

Currently, the following three global navigation satellite systems (GNSS) offer line-of-site radio navigation and

positioning, velocity, and time services on a global, all-weather, 24-hour scale to any user equipped with a GNSS

tracking receiver on or near the Earth’s surface:

• GPS – the Global Positioning System maintained and operated by the United States Department of Defense. For

information on the status of this system, visit the US Naval Observatory website (http://tycho.usno.navy.mil/) or

the US Coast Guard website (http://www.navcen.uscg.gov/).

• GLONASS – the Global Navigation Satellite System maintained and operated by the Russian Federation

Ministry of Defense. For information on the status of this system, visit the Ministry of Defense website

(http://www.glonass-center.ru/frame_e.html).

• GALILEO – an upcoming global positioning system maintained and operated by Galileo Industries, a joint

venture of several European space agencies working closely with the European Space Agency. Unlike GPS and

GLONASS, this is a civil endeavor and is currently in the development and validation stage. For information on

the status of this system, visit the Galileo Industries website (http://www.galileo-industries.net).

Despite numerous technical differences in the implementation of these systems, satellite positioning systems have

three essential components:

• Space – GPS, GLONASS, and GALILEO satellites orbit approximately 12,000 nautical miles above Earth and

are equipped with a clock and radio. These satellites broadcast digital information (ephemerides, almanacs,

time&frequency corrections, etc.).

• Control – Ground stations located around the Earth that monitor the satellites and upload data, including clock

corrections and new ephemerides (satellite positions as a function of time), to ensure the satellites transmit data

properly.

Summary of content (8 pages)

PAGE 1
DRAFAFT Chapter 1 Introduction The GRS receiver is a single-frequency, GPS+GLONASS L1 L2receiver and hand-held controller built to be the most advanced, compact, and portable receiver for the GIS surveying market. An integrated electronic compass and digital camera make the GRS an all-purpose, GIS field mapping unit. The GRS receiver is a multi-function, multi-purpose receiver intended for precision markets.
PAGE 2
Introduction • User – The community and military that use GNSS receivers and the corresponding satellites to calculate positions. Calculating Absolute Positions When calculating an absolute position, a stationary or moving receiver determines its three-dimensional position with respect to the origin of an Earth-Center Earth-Fixed coordinate system. To calculate this position, the receiver measures the distance (called pseudo-ranges) between it and at least four satellites.
PAGE 3
• Availability – The availability of satellites affects the calculation of valid positions. The more visible satellites available, the more valid and accurate the position. Natural and man-made objects can block, interrupt, and distort signals, lowering the number of available satellites and adversely affecting signal reception. • Integrity – Fault tolerance allows a position to have greater integrity, increasing accuracy.
PAGE 4
Introduction • Multipath reduction • Wide area augmentation system (WAAS) • Single-frequency static, kinematic, and differential GPS (DGPS) survey modes • Setting different mask angles • Setting different survey parameters The integrated 1.3 megapixel camera is used taking pictures of surveyed objects or survey sites. Getting Acquainted with the GRS The GRS is an integrated field controller and 50-channel GPS receiver with an internal electronic compass and digital camera.
PAGE 5
• The display screen and touch panel provides a graphical and tactile user interface for the unit. • The power button turns the receiver on and off. • The ESC (escape) button exits from the current screen or function. • The ENT (enter) button applies settings, numerical values, and records points (depending on the settings of internal software). Pressing this button for one second activates the controller’s Windows Start menu.
PAGE 6
Introduction GRS Ports The GRS has the following three ports: • USB – used for high-speed connection to a computer via ActiveSync. • Serial – used for communication between the internal GPS module (port A of the module) and an external device.Power – used to connect the GRS to an external power source. This port can also be used to charge the batteries. USB Serial (port A) Power Figure 1-5. GRS Ports SD Card Slot The SD (secure digital) slot provides extended memory for the controller (SD Card Slot).
PAGE 7
Integrated Camera The integrated 1.3 megapixel camera can be used for taking pictures. Camera Figure 1-7. GRS Camera External GPS Antenna Connector The external GPS antenna connector allows an optional external antenna to be connected to the controller for External GPS Antenna Connector post-process survey applications. Figure 1-8.
PAGE 8
Introduction Optional Accessories Table 1-2. GRS Op gives a brief list of optional accessories that can be used with the GRS. Contact your dealer to purchase optional accessories. GRS Optional Accessories Accessory Illustration External GPS Antenna and Cable Connecting an external PG-A1 GPS antenna increases the range of the GRS. Serial cable Connects the GRS to an external device (controller or computer) for data transfer and receiver configuration. NOTE:A ferrite core is attached to this cable.