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Handheld Outdoor Receivers
| Applications | |
|---|---|
| Title | Handheld Outdoor Receivers |
| Edited by | GMV |
| Level | Basic |
| Year of Publication | 2011 |
The Handheld Outdoor Receivers are devices conceived for outdoor navigation. The handheld GNSS units are self-contained devices which can vary somewhat in size. The smallest ones are about the size of small cell phones. The largest ones are the size of a typical television remote control[1].
These portable devices are used mostly for hiking and hiking-related activities such as hunting and geocaching. The rural environments where the equipment is typically used are areas where the surrounding vegetation and orography often block GNSS satellite signals. In environments where there is a clear line of sight to the satellites, GNSS technology is able to provide location with good accuracy and continuity of service.
Product Description
In contrast with road navigation, the outdoor navigation usually take place in rural environments.
In terms of equipments, the Handheld Outdoor Receivers usually have replaceable batteries that can run for several hours, making them suitable for activities far from an electric power source. The cases are rugged and some are also water resistant.
The handheld units’ screens are commonly small and the early handheld devices did not display maps and had monochromatic displays in order to preserve power. Nowadays, handheld outdoor receivers can be found with large sunlight displays, camera, powerful processors, field-swappable battery, compass and pre-installed embedded software able to show interactive maps, points of interest (or waypoints), route information and step-by-step routing directions. Many handheld receivers fully support WAAS and EGNOS.
The applications for which handheld outdoors receivers are used are considered as non-critical applications, although they can be used on emergency situations, for instance in isolated areas, where the ability of GNSS to provide a precise position can enhance the chances of rescue when hikers are disabled or lost. This situation requires a separate mean of communication with the rescue first responders.
The accuracy required by these applications is low. The current accuracy provided by civilian GPS is enough for these applications. Availability, however, can be reduced by heavy foliage and deep canyons in this type of environment.
Waypoints
The most important feature of a handheld outdoor receiver is Waypoint Navigation. A waypoint is a physical location determined by GNSS coordinates. On Waypoint Navigation the handheld unit determines the user location and indicates to the user the direction to follow in order to reach the waypoint. The route or track is mapped out using a series of waypoints so the user can navigate from one to the next and so on, like following a trail of virtual breadcrumbs.[2]
Handheld outdoor receivers let the user know where he actually is located and use waypoints to register where he had been, and where he wants to go. Capturing user position as a waypoint while navigating in a outdoor location, is where the waypoint concept is most useful[2].
The handheld receivers give the user the possibility to input and save many waypoints right on the device during the hiking activities, saving them as a Track. The waypoints can also be uploaded onto the device through external computers or PDA's.
In that way, the user knows exactly how to get back, due to the Track Log Recording, Return Back, Compass and Altimeter features, further detailed in here.
The waypoint concept can also support other type of task such as Photography Geocoding, geocaching, or for instance define a waypoint for a specific geographic feature found during hiking activities.
Product Characterization
Typically handheld outdoor receivers don't have external attachments. Although, some receivers models can run on external power, (e.g., from a car), connect to an optional external antenna through a jack or connect to a laptop or PDA for expanded uses[1].
From a technical perspective Handheld Outdoor Receivers were one of the most simple but revolutionary navigation devices since they were among first commercial GNSS products for personal use. In practical terms, the receiver simply points a straight line towards the next waypoint in the track (loaded or recorded by the user). Originally the first handheld outdoor receivers had no map support and the display was a simple monochromatic screen with low battery consumption. Nowadays the user interfaces features can vary substantially, from simplistic to powerful user interfaces, but usually the screens are able to show satellite constellation, maps, electronic compass, bearing or heading screen, coordinates, tracks with details, speedometer and odometer.
Some handheld outdoor receivers’ products are conceived to be used in golf activities, providing a set of features such as field information, distances, obstacles and even the registry of all strokes, including distance and power. These devices give to the players the possibility to get real time contextualized information and also to keep a complete database of performances linked with the golf courses.[3]
Another branch of handheld devices, the Marine Handheld receivers, are design for maritime navigation. Those are waterproof, rugged devices with floating capability and screens conceived to be visible in harsh conditions and direct sunlight, displaying the position, speed, bearing and aids to navigation buoys, among other informations.[4]
Product Examples
Handheld outdoor receivers that fit in this category are[5]:
- Garmin on the trail products
- Lowrance outdoors products
- Magellan outdoors products
- Bushnell GPS products
- DeLorme rugged products
Some of these brands also own lines of golf and marine handheld products.
Notes