What’s the difference between using a high gain antenna, and amplifying a lower gain antenna? Is the only benefit power?
Additionally who is the #1 antenna manufacturer in the industry? Our company has been using radiowaves for the most part and they’ve been sufficiant, but is there anything better?
Furthermore, can anyone recommend any quality reading material or reference guides on RF.
We’ve been quite happy with Pacific Wireless antenna products. Their sector antennas are excellent value for the money.
Our only complaint w/Pacific Wireless is their spotty and inconsistent use of stainless aiming hardware. We’ve got quite a few of their 5.8ghz solid dishes in use and while they’re happy away from the ocean, we’ve got a number of sites exposed to salt spray and the aiming hardware for Pacific Wireless solid dishes in those locations corrodes distressingly fast. Zinc chromate is completely inadequate for that environment; the helicals deterioate and adjustments become difficult after a few months of exposure. The dishes themselves are aluminum and will probably last quite a while.
Contrast the Pacific Wireless solid dishes w/their sector antennas, where what’s not UV stabilized plastic (radomes) is 100% stainless and pretty much immune to corrosion.
Our worst corrosion scenario so far was a customer’s Pacific Wireless 2.4ghz 24dBi grid where the feed arm corroded through and dropped off after about 13 months continuous exposure to salt spray.
If the distribution of nodes permits it, higher gain is better than more power.
A higher gain antenna concentrates your power over a smaller area, reducing your coverage. But, it’s “clean” gain, it gives you the same benefit in both directions, and does not add any noise of it’s own. Also, by reducing the coverage area, you reduce your exposure to other noise sources, making it a win-win (so long as you aren’t aiming for wide-angle coverage).
Amping a lower gain antenna increases the output power over the same coverage area, making the signal easier to recieve by the remotes. Unfortunately, gain from amps is “dirty”, the amp itself will add a few dB of noise, and the benefit is usually only in the transmit direction. The recieve gain those amps boast is only useful in a very low-noise environment, since it brings the noise level up just as much as the signal level, and adds a bit of it’s own noise, leaving you with a worse SNR on the recieve side.
An amped system may be easier to setup and use, but it is rarely a good move in the long run. When designing links, one will almost always be better off with a higher gain antenna. Amps should only be used if you have a very compelling reason, and fully understand the consequences. They can be useful, but most of the time they are used wrong (put on a sector, or omni, for example).
Radiowaves antennas are usually very good, they are amoung the better brands out there. Gabriel, RFS, and TIL-TEK are around the same level. A step down, and you will find the likes of Maxrad and Andrew. Further down the line are the likes of Antenex, Cushcraft/PAC-Wireless, and Mars. Then there is the cheap stuff, whos names escape me at the moment. (this was by no means a comprehensive list).
We usually use Radiowaves or RFS for backhauls and important customers, and switch to Gabriel when we need a really clean beam. For average customers we have mostly used Andrew, but recently (since merging with Cushcraft) PAC-Wireless has been supprisingly good for how cheap they are.
–Eric