Ubiquitous wireless connectivity in the home has become almost as "normal" as having AC outlets everywhere and perhaps more so. But due to the size, shape, and construction of many living quarters, there are likely to be weak or even dead spots where the signal is weak, unreliable, or noisy. The result in limited or no connection, especially as higher BER results in more retransmissions and lower throughput.
I had this problem several years back between my wireless router and a desktop PC located about 30 feet (10 m) away. Fortunately, there was a simple solution, as the PC's wireless adapter had an SMA coax connector for an external antenna. I bought a D-Link ANT24-0700 7-dBi 2.4-GHz omnidirectional indoor antenna for about $15, Figure, with its 5- foot (1.5 m) cable and reverse SMA connector (not familiar with those?—it's a subtlety due to FCC regulations), removed the adapter's supplied antenna, connected the D-Link unit, then moved it around. In a few minutes I found a micro-location where the signal was about 20 dB better than that of the wireless adapter’s own external antenna. The result: problem solved at low cost, low headache, and little time, without software configuration issues, operating system compatibility, or checking for updates; it was truly "plug and play."
The D-Link ANT24-0700 external antenna with cable easily solved the problem of poor wireless signal, and at low cost in dollars, time, and frustration.
All that changed when I recently replaced that desktop PC unit. This PC had a pair of diversity antennas lacked any coax connector for an external antenna. Again, wireless performance was erratic and the link often timed-out to due weak received signal and high BER. While diversity antennas can be a good thing, in this case, the path between the wireless router and the PC was blocked by several metal cabinets, thick plaster walls and other signal-attenuating obstacles.
This time, though, the easy solution of adding that external antenna was no longer an option. So I did the research on Wi-Fi extenders, which range from about $35 to $150, analyzed the pros and cons of the model based in their vendor description as well as customer reviews, and looked at their purported ease-of use in setup and configuration, and bought one that seemed to be a good fit.
Long story short: neither the quick, five-minute setup mode it offered, nor the alternative twenty-minute mode worked. The good news is that after about two hours trying various things I somehow – not sure how – got the range extender to work via a combination of skill, persistence, and largely luck. Bottom line is that not having the antenna option removed the option of a non-brainier solution and transformed it into a much more complicated one.
I can speculate as to why the adapter's external antenna and its connector were replaced by a diversity antenna: it satisfies many customer’s needs, it means one less thing that can be connected and so cause problems, and they are a very good design choice for laptop PCs, which by definition are moved or reoriented. Although I don’t have the numbers, I suspect it is not cost, as the BOM and assembly difference between an internal diversity antenna and an external coax connector one seems almost trivial.
But for fixed-in-place desktop unit, even a diversity antenna may not be enough; it certainly wasn’t for my case. If there are specific obstacles in the straight-line path and no good alternative paths, diversity may not be able to help while the external-antenna option can.
I was fortunate, as my modest expenditure of time and money for a low-end range extender solved the problem. Still, I would have liked to have the no-headache, no-hassle, flexible option of that movable external antenna.
Have you ever bought a replacement or newer product and found that a small, useful feature (hardware or software) is no longer offered? Or have you ever designed this sort of “upgrade” that contains less or possibly aggravates some percentage of users?
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