Wireless Performance - Throughput vs. range
Because I've tested draft 11n products using the other available chipsets on the Azimuth W-Series WLAN Test Platform, I also used it for the N1 to gauge its throughput vs. range performance instead of my usual multi-location walk-around test. You can read more about the Azimuth system and the test method in Draft 802.11n Revealed: Part 1.
The plots shown below use the same data as shown in the previous article, with the N1 data added. I should note that due to the N1's dropout problem, I had to use 30 second IxChariot test runs in order to get results that didn't swing all over the place and switch to using 3 dB attenuation steps to complete the testing in a reasonable amount of time. The other plots shown use 5 second IxChariot tests and 1 dB attenuation steps.
Figure 21 shows downstream/downlink performance of products using the Atheros xspaN, Marvell TopDog and Broadcom Intensi-FI draft 802.11n chipsets. Performance for an Airgo Gen 3 chipset-powered product is also included, although it's not a draft 11n chipset.
Figure 21: Azimuth Downstream Rate vs. Range comparison (click to enlarge)
The good news in Figure 21 is that although the N1's throughput doesn't aproach that of the RangeMax 240 and Linksys Wireless-N, it doesn't drop off as quickly. It also maintains a downlink connection at high path loss values (i.e. lower signal levels) than the Linksys Wireless-N / Broadcom and has a curve closest to the best-performing Netgear Rangemax 240 / Airgo Gen 3.
Note that the 60 Mbps average throughput at lower path loss levels is better than the 43 Mbps result in the 1 minute downlink test (Figure 15). This is probably due averaging differences over the 30 second vs. 2 minute test periods.
But the N1 doesn't fare as well in the upstream / uplink plot (Figure 22). For some reason, best-case uplink throughput dropped down closer to the ~40 Mbps 2 minute average value. But once again, the N1 maintained a connection longer than the Broadcom-based product and its throughput held up better at lower signal levels.
