Archive for the ‘Handheld GPS’ Category
Nothing is more enjoyable than hiking, backpacking, and camping in the great outdoors. But with the beauty of Mother Nature also comes a few potential dangers. It’s important to be prepared to deal with adverse weather conditions, wild animals, and injury far from civilization. To deal with adverse weather, it’s important to dress warm, and also have extra dry clothes and rain gear. Most wild animals are not dangerous and will avoid humans, but one potential danger can be bears, and thus when traveling in several wooded locations bear pepper spray is essential. To address injury, it’s important to carry a first aid kit, and also to have a compass or handheld GPS to get back fast if necessary and avoid becoming lost.
By taking these precautions you’re sure to have a wonderful and safe time in the outdoors. Remember, though there are potential dangers, by being prepared you’re sure to feel safer and have a lot more fun.
The first satellite navigation system, Transit, used by the United States Navy, was first successfully tested in 1960. Using a constellation of five satellites, it could provide a navigational fix approximately once per hour. In the 1970s, the ground-based Omega Navigation System, based on signal phase comparison, became the first worldwide radio navigation system. GPS requires the equations of general relativistic corrections to these atomic clocks in satellites for sufficient accuracy. The general relativistic equations correcting signals of atomic clocks in satellites were first published in 1956 by Friedwardt Winterberg.
The design of GPS is based partly on similar ground-based radio navigation systems, such as LORAN and the Decca Navigator developed in the early 1940s, and used during World War II. Additional inspiration for the GPS came when the Soviet Union launched the first man-made satellite, Sputnik in 1957. A team of U.S. scientists led by Dr. Richard B. Kershner were monitoring Sputnik’s radio transmissions. They discovered that, because of the Doppler effect, the frequency of the signal being transmitted by Sputnik was higher as the satellite approached, and lower as it continued away from them. They realized that since they knew their exact location on the globe, they could pinpoint where the satellite was along its orbit by measuring the Doppler distortion.
Initially the highest quality signal was reserved for military use, while the signal available for civilian use was intentionally degraded (“Selective Availability”, SA). Selective Availability was ended in 2000, improving the precision of civilian GPS from about 100m to about 20m. In a contemporary sense, GPS is used often in vehicles and portable devices like the Bushnell Handheld GPS.
While we often look at camping as an excellent opportunity to ârough itâ for a week or a long weekend, there are actually a number of technological advances that have made the experience more pleasant. Take for example the hiking tent â a lightweight, sturdy-construction shelter that can be lifted and carried for long distances on oneâs back. The cold-rated sleeping bag is another example; over time, weâve learned that the more loft inside the bag, the warmer weâll stay.
Perhaps the most useful technological stride that the camping industry has seen in recent years has nothing to do with comfort and everything to do with navigation. Handheld GPS units can get lost hikers back on track when they stray too far from the beaten path. Itâs also invaluable to know your geographic coordinates in case it becomes necessary to call for help. The authorities will be able to reach you in an expedient manner.