+alma Posted November 22, 2005 Posted November 22, 2005 a friend has just told me that satallite coverage is not very good in winter and reception is much poorer than in summer and not to expect to much from my gps in winter .is this true? Quote
barryhunter Posted November 22, 2005 Posted November 22, 2005 (edited) I've never heard that but doesnt mean it isnt true. The only reason I can think of is in the winter the weather is likly to be worse. Cloud cover will affect GPS signal quality, however I think the difference is minimal. Probably better in winter as there is less tree cover ;-) Edited to add: its not quite winter but noticed no differnce in GPS quality today! Also battery performance will suffer slightly in the colder weather, but just carry a spare set kept in an inner pocket, and swap the batteries if the GPS doesnt power up or complains of low battery. Edited November 22, 2005 by barryhunter Quote
+Birders Posted November 23, 2005 Posted November 23, 2005 Sounds like a leg-pull but ask him/her to explain their reasoning then post that on here. Quote
+Moote Posted November 23, 2005 Posted November 23, 2005 (edited) If as I assume the satellites transmit in the microwave band then there would be a greater absorption of the radiation; due to the higher amount of water in the atmosphere. Edited November 23, 2005 by Moote Quote
+The Forester Posted November 23, 2005 Posted November 23, 2005 is my leg being pulled Yes. a friend has just told me that satallite coverage is not very good in winter and reception is much poorer than in summer and not to expect to much from my gps in winter .is this true? No. As has been said above, you will get better reception under deciduous tree cover in winter than in summer. Quote
+Lincolnshire Mountaineer Posted November 23, 2005 Posted November 23, 2005 "If as I assume the satellites transmit in the microwave band then there would be a greater absorption of the radiation; due to the higher amount of water in the atmosphere. " No they don't and so consequently, no there isn't! Quote
+Chris n Maria Posted November 23, 2005 Posted November 23, 2005 I always thought they worked better in the winter - because there are no blooming leaves on the trees. Chris Quote
+Moote Posted November 23, 2005 Posted November 23, 2005 (edited) "If as I assume the satellites transmit in the microwave band then there would be a greater absorption of the radiation; due to the higher amount of water in the atmosphere. " No they don't and so consequently, no there isn't! Been reading up about this most of the day and discovered that civil GPS systems transmits in the L1 frequency band of 1575.42 MHz in the UHF band. UHF's shorter wavelengths are more susceptible to absorption by liquids, therefor there is greater absorption in winter. Milton Edited November 23, 2005 by Moote Quote
+walkergeoff and wife Posted November 23, 2005 Posted November 23, 2005 "If as I assume the satellites transmit in the microwave band then there would be a greater absorption of the radiation; due to the higher amount of water in the atmosphere. " No they don't and so consequently, no there isn't! Been reading up about this most of the day and discovered that civil GPS systems transmits in the L1 frequency band of 1575.42 MHz in the UHF band. UHF's shorter wavelengths are more susceptible to absorption by liquids, therefor there is greater absorption in winter. Milton Your numbers are right, but the resonant frequency of water (and therefore the frequency at which it aborbs most radiation) is about 2.3GHz, and that is the frequency used by Microwave ovens. Quote
+Moote Posted November 23, 2005 Posted November 23, 2005 Your numbers are right, but the resonant frequency of water (and therefore the frequency at which it aborbs most radiation) is about 2.3GHz, and that is the frequency used by Microwave ovens. I used the phrase "more susceptible to absorption" this was taken from articles I have read on several websires including garmin.com and physics.org. From my extesive day of non-working the conclusion that I draw is that light radiation above 800MHz has a greater absorption rate by all water based liquids. Quote
+walkergeoff and wife Posted November 23, 2005 Posted November 23, 2005 Your numbers are right, but the resonant frequency of water (and therefore the frequency at which it aborbs most radiation) is about 2.3GHz, and that is the frequency used by Microwave ovens. I used the phrase "more susceptible to absorption" this was taken from articles I have read on several websires including garmin.com and physics.org. From my extesive day of non-working the conclusion that I draw is that light radiation above 800MHz has a greater absorption rate by all water based liquids. I wasn't disputing your general conclusion - perhaps I was saying 'Isn't it a good job that GPS doesn't run at 2.3GHz!' Quote
+The Blorenges Posted November 23, 2005 Posted November 23, 2005 Well, I'm glad you've cleared that up... I'll never boil MrB's GPSr in the microwave..... Quote
+Jonovich Posted November 23, 2005 Posted November 23, 2005 So all this global warming is down to pigging satelites slowly cooking the planet? PING.... We're done J Quote
+Gralorn Posted November 23, 2005 Posted November 23, 2005 I must admit that I only really understood the shivering bit!!!!!!!!!!! Quote
Morseman Posted November 26, 2005 Posted November 26, 2005 "If as I assume the satellites transmit in the microwave band then there would be a greater absorption of the radiation; due to the higher amount of water in the atmosphere. " No they don't and so consequently, no there isn't! Actually, they are just in the microwave bands - 1.2 to 1.5GHz Many people, wrongly, think that 'microwaves' are classed as being where the microwace ovens operate, which is 2.4GHz. However, the official starting point for microwave bands is 1GHz. The water absorbtion is unlikely to make much of a difference as experience tells me that GPS receivers still work in the pouring rain! As has been said, tree cover and buildings can make far more of a difference to reception, so your leg is being pulled. Quote
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.