Please not that I did not recommend using an omni antenna. I only offered it as an option.
That's correct. However, I can't tell from the description where the access point is located relative to ALL the users. A 10dBi panel antenna will have a beamwidth of about 60 degrees which is more than enough to cover the entire house. However, if the garage user is located behind the antenna, there will be problems. I've done indoor directional antennas, but only when the radios are at the ends of house and the antenna is pointed inward. Working from the back of a panel antenna does not work very well.
True. I'll dig out my notes and run some calculations on the theoretical maximum sensitivity at 10^6 BER for various modulation schemes and data rates. What you'll find is that most of the chipsets advertise RX sensitivities that are very close to the noise floor. Unless someone comes out with a cryogenically cooled front end, the current crop of GaAsFET front ends are about as sensitive as can be. Incidentally, when I was doing bench tests for sensitivity and other specs, I found that the digital noise sprayed all over the circuit board by the non-RF parts of the circuit had a substantial effect on the receive sensivity. On the better boards, with little digital noise to ruin my tests, the variation in measured sensitivities over a production lot was as bad as 6dB. These were basically rejects as the bulk of the test boards were within a 2dB spread.
So, lets see if the numbers make sense. The worst case sensitivity deterioration that I saw was 6dB (in dBm not dBv). Yet the suggested power amplifier will go from +17dBm to +30dB or an increase in 13dB TX gain. However, the receiver sensitivity only varies 6dB so we have anywhere between 7 and 13dB of overkill in one direction. I don't think that cranking up the tx power to compensate for a crappy receiver is going to do much good.
I like your list better except for the repeater and range extender issue. Incidentally, if you had specified a WDS repeater, I might be a bit less venement about my hatred of repeaters.
A variation of this is to seperate the access point (radio) from the router/modem section. The problem is that the conglomerated modem/router/access-point devices want to live where all the wires tend to come together. That's usually in the basement, in a closet, under a desk, or other places where hiding the wires is practical.
However, the radio does not work very well buried in these locations. Therefore, by seperating the radio section (access point) from the rest of the boxes, there's quite a bit more versatility in locating the box and antenna. Up high, on a bookshelf is a good place. There are only two cables (power and ethernet) required so wiring isn't as bad as to a modem/router which has many more cables involved. It also has the advantage of allowing easy replacement of the radio section when the next generation of acronyms appear on the market.
Linksys makes SM01 mounting plate for their plastic boxes. Costs about $2/ea. |
As you noted with the WG511, it's somewhat difficult to differentiate between the good stuff and the junk. I'm in the biz and I get fooled a bit too often.
I would repeaters and range extenders in the desperation category.
That's what I would do first or 2nd. Not because it's the best solution but because it's one of the easiest to try and probably the cheapest.
A repeater will also piss them off if they're within range by doubling the amount of traffic floating in the air. However, at least the repeater only trashes one channel. However, the 2nd access point could easily be on the same channel as the main wireless router if (and only if) they are sufficiently seperated and isolated from each other so as not to interfere with each other.
Yep. Also impossible to add external antennas.
Well, they are a pain but not bad it you're willing to tolerate some directionality. Most users will NOT tolerate directionality on devices like cell phones, where a change in user position can easily result in a dropped call. If the directionality is really obvious, like a panel antenna plastered on the back of a laptop lid, methinks most users can figure out where to aim it. If the laptop or PDA is too small for a decent directional gain antenna, then I agree, it's impractical.
(I have some antenna design ideas and few prototypes that methinks may be practical, but nothing that will work for every possible client radio or attached computer/PDA).
Thanks. At least we agree on one out of nine items.