A “reflector” antenna element is nothing new, they are quite standard in many configurations, including a “Yagi” which I regularly used to communicate with amatuer sattelites.
The critical parameter is actually 1/4 of the wavelength, although 1/2 and full-wave are better, they are often impractical for, say, a 2-meter band. In the case of cellphones (correct my math if I would smash a probe into Mars-- (1 / ~900Mhz) * c = .33 meters (taking ‘c’ to be 300,000,000 meters/sec). Don’t see cellphones with foot-long antennas, do ya
at least not anymore.
Okay so what? Antenna theory, despite the best intentions of mathematical geniusus, remains an analog-electronics guru-science in many ways. I don’t pretend to understand why one particular smashed-together bunch of metal recieves band X better than any other kind.
It sure doesn’t make intuitive sense. I have two cellphones, one is made of Magnesium (An ericcson DF388) and the other plastic (Motorola StarTac). Needless to say, both contain all manner of irregularly shaped metal hunks. What difference could one more or less make? unless it were directly connected ot the antenna, or very carfully tuned and placed an exact distance from it.
I read that study and it sounded… wrong somehow. Like how an un-scientific person thinks scientists do things. There is a lack of a really measureable output for one, for another they leave out important details like what kinds of phones were compared, what the antenna configurations were, what the battery strengths/lives were.
Having said that I have no reason to doubt the well-meaningness of the study, but the point is extremely well taken- these things are easy to make, why are cellphone manufacturers not putting them into their phones?
I have to assume the answer is that they are. Let me be clearer- It is in a cellphone vendor’s best interest to make a compact antenna as strongly as possible. It would be their bread and butter. So I have to assume that batallions of very very smart EE-type people have analyzed this problem to death, and continue to do so. And if a stick-on piece of mylar (or whatever) made a difference, I presume it would be added, and further that it would be on the inside of the case.
I would also presume that the specifics of antenna designs in this ultra-competitive industry are trade secrets. I don’t expect many of the engineers involved could talk about it even if they knew.
Which leaves us back where we started… Human perception being as lousy and hopelessly subjective as it is, and cellphone performance metrics being vague and nebulous for the casual user (‘bars’ of signal? as an embedded systems programmer I can tell you thats useless… I might be tempted to make it a log scale, or lie to make the customer feel better, or heck it might just be a guess based on clumsy signal/noise reading in the audio)… I don’t know if a simple answer is possible, and can certainly explain the proliferation of claims.
Anyone have difinitive evidence?
-Curt