Pros: Provides both omni-directional and directional antennas
Cons: Omni antenna can’t be turned off, leading to signal leakage
When setting up a wireless network for home or office, it’s not unusual to have so-called dead spots where the radio signal doesn’t reach. Conversely, chances are that your WLAN signal will likely spill over to an area you don’t intend it to, like a neighbor’s property. IOGear aims to address this problem with a WLAN product, the $89.95 Wireless-G Broadband Router (model GWA502), which employs a dual-antenna configuration the company dubs “Super-Fi”.
Like all similar products in this class, the GWA502 offers the de rigueur omni-directional external dipole antenna. In addition to the mast, however, the GWA502 also provides an internal directional patch antenna to help reach those hard-to-reach spaces that most of us (especially in larger or otherwise challenging environments) inevitably encounter.
The augmentation of a standard omni-directional with a directional patch antenna has some clear advantages. In multi-story buildings, a directional antenna lets you point a strong signal to the floor above where the router is located, where an omni-directional antenna may not reach well.
Even in single-story structures, most SOHO users are likely to place a WLAN router where their broadband connection enters the building (often on an exterior wall). In this common scenario, an omni-directional antenna may have difficulty penetrating the entire structure while doing a good job of providing signal in unwanted areas like your side yard, parking lot, or even your neighbor’s premises. In contrast, a patch antenna can do a better job of directing the signal inward where you want it and minimizing signal “leakage”.
Setting up the GWA502 out of the box was quick and painless. Once you configure your IP address to match the unit’s subnet, you can get the router up and running with a minimum of muss and fuss by selecting “Typical” settings. This calls up a six-step software wizard that walks you through all of the important settings. It will also attempt to make setting up the firewall a smidgen easier, by offering three overall settings– DISABLE, LOW, and HIGH– and displaying how each configures the nine individual firewall settings. The differences between the low and high settings are essentially whether outbound traffic and ICMP responses are permitted.
One minor annoyance is if you use the wizard and want to enable wireless encryption, you must either configure WEP or leave it off. After completing the wizard, you can go and select another form of encryption and authentication like WPA and 802.1X.
In the category of LAN features, the GWA502’s biggest weakness is its paucity of logging and monitoring functions. It offers an event log that can be saved but not exported, and there is no e-mail alerting feature. The GWA502 does provide remote admin access.
People who consider a GWA502 purchase will almost certainly be attracted by the unit’s integrated directional antenna. Of course, directional antennas can be added to some other WLAN routers, but not all antennas can be removed and replaced, and even when they can be, there is still the additional cost of the antenna and perhaps a cable as well.
Because the patch antenna is internal to the GWA502, the only way to position it is to position the router itself. The patch antenna is arranged so that the directional signal is emitted from the top of the unit, so placing the GWA502 in a horizontal position (flat on a surface) will point the signal upward, while setting the unit on one edge (with a included rubber stand) will let you aim the antenna anywhere on the X or Y axis.
While the availability of a patch antenna should give users a great deal of control over where their WLAN signal goes, as currently implemented in the GWA502 it leaves something to be desired.
Both the omni and the patch antenna can be used simultaneously, which will be useful in some cases– especially in the multi-story scenario described above, or if you’re just trying to push a signal to the far reaches. However, if you’re trying to keep your WLAN signal within the confines of your building, having the omni broadcasting will largely defeat the benefit of the patch antenna’s focused signal profile.
Therein lies the problem, because the GWA502’s omni antenna can not be disabled via the unit’s firmware. Moreover, the antenna is fixed to the unit and thus can’t even be disabled by removing it. The antenna is mounted on a spring-loaded post and can be pushed in and recessed against the unit (which might degrade, though not eliminate, its signal), but this isn’t an option if you have any wired clients, since doing so completely blocks the GWA502’s four Ethernet LAN ports. (IOGear says disabling antenna diversity will be possible in a future update.)
As expected, I found the current inability to take the omni-directional antenna out of the equation made it difficult if not impossible to focus the signal with the patch antenna. I used a Dell Inspiron 300m notebook with a built in Broadcom a/b/g chipset to measure the GWA502’s signal strength from a half-dozen locations in and around my home. (Since signal strength constantly fluctuates, the figures below are all approximate.)
I began by setting up the GWA502 against an exterior wall and in its standard orientation: horizontal with the omni antenna fully extended and perpendicular to the unit. In this orientation, I recorded signal strength ranging from a high of -38 dBm to a low of -82 dBm at various points. Perhaps most importantly, I measured a -65dBm signal while standing outside the window at my property line, separated from the router by concrete block, glass, and about 12 feet.
I then changed the GWA502 orientation to vertical, so that its patch antenna was pointing toward the inside of my house. Since the omni-directional antenna could not be disabled, I arranged it parallel to the unit. (Note: An inevitable by-product of this arrangement is that the omni antenna directs its signal above AND below. This could possibly be a concern for apartment dwellers, or perhaps be very useful if you were trying to get a signal to other floors on either side of the router.) Predictably, the signal strength in rooms directly in the wake of the antenna rose — for example, from -38 dBm to -12 dBm in the room the router was in, and from -50 dBm to -35 dBm in the room adjacent to it. Signal strength in other rooms was essentially unchanged from that provided by the omni antenna.
However, back outside at the property line, the signal strength was also unchanged — still at about -65 dBm. Since this is some distance behind the patch antenna, I would have expected little to no signal. My logical conclusion was that I was picking up the omni antenna’s signal which was still penetrating escaping the building.
I took additional measurements from the same location with the omni-directional antenna clicked into its recessed resting place, but there was no substantial reduction in the signal strength — I was still able to acquire a strong signal. I also set up the GWA502 in a similar way in another building that afforded me the opportunity to get much further away (about 60 feet) from the patch antenna’s “bad” side, but I was still able to access the WLAN with a weak albeit stable signal.
[IOGear tells us that a firmware upgrade to come in the fourth quarter of 2004 will allow users to turn off the omni-directional antenna.]
If you’re looking to maximize your signal’s footprint in one direction or give your WLAN signal more elevation in a multi-story building, then the GWA502 may work quite well for you. However, if your main concern is to shape and control the confines of your signal, the GWA502 will likely prove a disappointment, at least until IOGear adds the ability to disable the omni-directional antenna.