Building Frequency Table Based On Spectrum Analyzer Results; Adding Bsr Frequency Table - Airspan ASWipLL Quick Installation And Configuration Manual

AS W i p L L 9 0 0 M H z
Building Frequency Table Based on
Spectrum Analyzer Results
Once you have established an initial wireless link between Base Station (i.e. BSR) and subscriber sites (i.e.
SPRs/IDRs) using the default ROM frequency table, you can define a new frequency table based on clearer
frequencies for better wireless communication based on the Spectrum Analyzer results.
When the Spectrum Analyzer graph displays "spikes", this generally indicates interference (i.e. frequencies
that should be excluded). Note that normal "noise" level is approximately –112 dBm (referred to as Thermal
Noise). Airspan recommends using frequencies that are approximately 28, 20, and 12 dB above interference
levels to effectively operate in 8, 4, and 2 level FSK (4 Mbps/3 Mbps, 2 Mbps, and 1.33 Mbps/1 Mbps),
respectively. ASWipLL can operate in 2, 4, and 8 level FSK with signal strengths greater than -90, -83, and -75
dBm, respectively.
In the unlicensed bands, Airspan recommends increasing frequency allocations as much as possible
between multiple BSRs with adjacent and overlapping sectors, or when using omni-directional antennas. This
prevents more than one BSR transmitting on the same frequency at any given time, which can result in radio
interference causing communication loss between BSR and its SPRs/IDRs. Airspan recommends a minimum
separation of 4 MHz between these adjacent BSRs. In addition, when operating in the ISM band, it is
recommended to use as many frequencies as possible to increase immunity to random interference.
Airspan allows you to define up to 32 NVRAM frequency tables using WipManage. These frequency tables
can consist of multiple frequencies for frequency hopping-based wireless communication. These NVRAM
frequency tables can be defined in WipManage using one of the following methods:
Normal: frequencies entered manually
Gap Algorithm: frequencies calculated automatically based on certain user-defined parameters
Notes:
1) For Normal frequency tables, the NVRAM frequency tables support a maximum of up to 388 bytes. Gap
frequency tables are unlimited with regards to bytes.
2) For normal frequency tables, at least 9 frequencies must be entered. Therefore, if less than 9 frequencies
are used, the frequencies must be entered repetitively (and in the same order) until at least 9 frequencies are
entered and the series is complete. For example, if only five frequencies are used, e.g. F1, F2, F3, F4, and F5,
the frequencies must be entered as such: F1, F2, F3, F4, F5, F1, F2, F3, F4, F5 (i.e. at least 9 entries -- in this
case 10 entries to complete the series).

13.1. Adding BSR Frequency Table

The first step is to add a frequency table for the BSR.
To add a Normal frequency table (using WipManage):
1. In the BSR Zoom window, from the Configuration menu, point to RF, and then choose NVRAM Frequency
Tables; The NVRAM Frequency Tables dialog box appears.
2. Click Add; The NVRAM Frequency Table Add dialog box appears.
13070311-02 Airspan Networks Inc.
13
Q u i c k I n s t a l l a t i o n & C o n f i g u r a t i o n G u i d e
31