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With a 400-milliwatt radio, the RangeLAN802 was the most powerful FH product we tested, and at 460 Kbps, it offered the best performance of any FH product in our long-distance walled-office range tests. While both Symbol's and BreezeCOM's products provided better performance than Proxim's in both our long-distance open-office and in-lab single-station performance tests, we found that Proxim's card performed better with Symbol's and BreezeCOM's APs. We attribute these performance deficiencies more to Proxim's AP than to its PC Card. Proxim and Symbol were the only two FH cards that offered full interoperability across all APs, and their average throughput scores of 930 Kbps were identical.

Even though Proxim has the most powerful radio of any product we tested, its power consumption in standard operating mode is only marginally higher than other FH products. Furthermore, Proxim and Symbol initially were the only ones to send us FH cards that supported power savings. Aironet and BreezeCOM sent us updates late in our testing that added power savings to their products, and Nortel plans to add the capability by April.

While we liked the RangeLAN802, we discovered some deficiencies. Although most vendors support a diversity antenna configuration, Proxim does not. This is not quite as big a limitation for FH products as it is for DS products, since the latter are considerably more susceptible to multipath interference. The snap-on antenna was the most compact one we tested, but Proxim should spend some time to improve its design. When we removed the antenna from one of the cards, part of the PC Card case came off with it. Proxim later informed us of some buttons on the card's underside that should be pressed when removing the antenna--but you need nimble fingers to do it. Pricing for Proxim's product is middle of the road.

Symbol Technologies Spectrum24 2Mbps PC Card
Symbol's Spectrum24 PC Card combines a solid hardware design, an excellent feature set and noteworthy client configuration facilities into a package that proved to be compatible with every AP in our tests. The only major drawback is its price: at $795, it defines the high end of the market.

We liked the included configuration utility, easily accessible from the properties menu within the Windows Network Neighborhood. It was significantly easier to use than other vendors' implementations. Symbol also supplies a site survey utility and other diagnostic tools.

Advanced features include a flexible power management capability, optional wired equivalent privacy and a micro-AP feature that lets any notebook act as a simple AP connecting other wireless devices to the wired LAN.

As noted, we were able to connect Symbol's PC Cards to all the other access points and performance was generally very good. The exception was with BreezeCOM's AP: the Symbol PC Card connected to it at only 1 Mbps. Throughput was only around 700 Kbps. We confirmed the problem with both Symbol and BreezeCOM, and both vendors were working on resolving it at press time.

In our multistation tests, Symbol achieved above-average aggregate performance at 1.06 Mbps. It also did well in our range tests, where it achieved an average performance of 860 Kbps--the best among FH products. But in our long-distance walled-office test, performance was only 200 Kbps, a speed exceeded by both Proxim and Aironet. We tested their 100-milliwatt versions, but Symbol also offers a product with an output of 500 milliwatts. We would expect much-improved range--but more power consumption--in this product.

Aironet Wireless Communictions PC3500 Frequency Hopping Wireless PC-Card Adapter
Aironet's PC3500 PC Card bears a close physical resemblance to the 4500 PC Card, except that it uses a FH radio rather than a direct-sequence one. Like the 4500, the 3500 has a well-designed removable antenna. Also like the 4500, it uses a counter-intuitive slow-flasing LED to signal association with an AP instead of the constantly lit LED that signals association with other products. While the drivers vary between the two cards, both are manageable via Aironet's WinDGS client configuration and management software. The PC3500 is competitively priced at $495.

As expected, performance was about 10 percent slower for the PC3500 than for the 4500 DS PC Card--but it was second only to Symbol among FH PC Cards. Performance in our range tests was mixed. On one hand, only Proxim, with its 400-milliwatt radio, outperformed the PC3500 in our long-distance walled-office test. But in our long-distance open-office test, the PC3500 was slowest of the 2-Mbps FH PC Cards.

Interoperability with other FH APs was among the weakest of all products tested. The PC3500 was the only card that was unable to associate at all with the BreezeCOM AP and while we were able to associate with the Nortel AP, we were not able to complete our FTP testing.

BreezeCOM BreezeNET SA-PCR PRO.11 PC Card
Employing a retractable di-pole antenna system, BreezeCOM offers the most innovative wireless PC card in the industry. Unlike some competitive products that have antennae extending beyond the edge of your notebook, the BreezeCOM card fits flush with the edge of the PC Card slot. And unlike other products that have removable antennas, BreezeCOM's PC Card has no extraneous parts. Whether the antenna can stand up to abuse is still up for debate, but its flexible design should minimize the possibility of breakage.

In addition, BreezeCOM is the only FH vendor to offer a 3-Mbps transmission mode that yields an effective throughput of approximately 1.8 Mbps. Since this mode is not supported by the 802.11 standard, we did not use it in our performance comparisons, but some customers will undoubtedly consider this to be a competitive advantage. Nonetheless, even at 2 Mbps, the BreezeCOM PC Card offers better performance than any other FH product.

The PRO.11 provided the best throughput in both our short-range closed-office test and long-range open-office test. Unfortunately, it could not maintain association with the BreezeCOM AP during our long-range closed-office test. We're not certain whether this deficiency is attributable to the PC Card or the AP, but it is worth noting that BreezeCOM's AP had smaller antennas than either Proxim, Aironet or Symbol. The vendor offers another card, the SA-PCD PRO.11, that has a larger, removable antenna that it claims increases range by 50 percent. BreezeCOM also sells an AP that has modular antennae.

From an interoperability standpoint, the BreezeCOM PC Card did not fare quite as well as the competition. The main issue we encountered was BreezeCOM's implementation of the radio's dwell-time period, the amount of time a FH device spends transmitting on a given frequency before hopping to another. After numerous phone calls, beta driver and firmware updates, and configuration changes to APs, we were able to achieve association with all of the other APs. While BreezeCOM's tech support defended their decision to limit the number of dwell options, we feel it would be better if the cards were agile enough to adjust to the AP dwell setting.

At press time, we were not able to complete our FTP tests when connected to the Aironet AP. However, both vendors indicated that successful interoperability is possible with an additional firmware upgrade.

Although we really liked the look and feel of BreezeCOM's configuration utilities, we experienced intermittent problems installing them on our Dell and HP notebook computers. Our attempt to upgrade firmware on one PC Card did not run to completion, so we had to replace it. In addition, the utilities were as well integrated as those available from vendors like Aironet. You'll need individual utilities for adjusting parameters, upgrading firmware and upgrading drivers.

Pricing for the PRO.11 is middle of the pack, as it is slightly more costly than Aironet and Nortel, but less than Proxim or Symbol. We feel this product has a lot of potential if BreezeCOM can correct some of the problems, likely the result of a relatively new design.

Nortel Networks BayStack 650 Wireless LAN PC Card
Nortel's BayStack 650 PC Card is physically identical to its DS cousin, the 660. It was the only card we tested that was limited to 1 Mbps. On the other hand, it was also one of the least expensive FH products we tested. The 650 shares a common driver base with the Bay 660, a feature you may find helpful if you need to support both products in a single environment.

Not surprisingly, the 650 offered the lowest overall performance of any product tested, slightly greater than half of that experienced with the 2-Mbps products. But from an interoperability standpoint, it stacked up relatively well, associating with all of the APs. However, its performance, when connected to Aironet's AP, was so slow that we could not complete our testing. The 650's range was surprisingly decent in light of its integrated PC Card antenna.