Frequently Asked Questions

Q: I see your WiMAX product is 802.16e, why is Azurecomm following this standard and what are the advantages of 802.16e over 802.16d?

A: The 802.16e standard is more recent and enhances the 802.16d standard to include many new features. Among these are: mobility up to 120 km/hr (75 mph), lower cost (802.16e is now the dominant standard and most products on the market will be 802.16e), 802.16e uses scalable OFDMA which allows scalable system bandwidth (802.16d uses OFDM), improved QoS and coding, improved coverage (optional MIMO and STC) and power reduction (sleep and idle modes).

Azurecomm consciously never pursued the 802.16d fixed standard and is solely focused on the mobile WiMAX 802.16e standard because we saw that 802.16d would eventually be overtaken by mobile WiMAX 802.16e.

Q: Is 802.16e compatible with 802.16d?

A: No, there is no compatibility between the two standards.

Q: My WiMAX application is fixed, why should I care about mobile WiMAX?

A: When the 802.16e mobile WiMAX standard was completed, the wireless industry shifted to this new standard. The mobile WiMAX standard will work fine for fixed applications. In addition to the advantages listed above, 802.16e equipment will be less expensive because, being the dominant standard, economies of scale will drive costs down. Where as with virtually all equipment manufacturers  moving away from the 802.16d standard, equipment prices will not drop like 802.16e mobile equipment. (Learn more here)

Q: Will WiMAX base stations provide ubiquitous coverage within the cell area?

A: This is highly doubtful - unless the terrain and environment are close to ideal, there will be coverage holes, shadowed areas and poor performance at cell edges.

Q: I see a lot of WiMAX equipment, how is Azurecomm's WiMAX solution different?

A: Azurecomm's AzureMAX product line was developed to address the sector fill-in market with a low-cost, lightweight, fully self-contained single sector base station to fill coverage holes.

Q: Can your product be used for applications other than sector fill-in?

A: Yes, we offer an option where four of our base stations can be mounted on a tower for 360 degree coverage. "Big Iron" base stations from Motorola, Alvarion, Aperto, etc., typically cost between $50k and $150k - Azurecomm can provide 360 degree coverage for a fraction of that cost.

Q: You say your radio is software-defined, why is that important?

A: Our radio uses fully reconfigurable DSP processors. This not only allows us to add features, optional WiMAX features and bug fixes but also to completely change the internal structure of our WiMAX engine by loading new DSP code.

Q: I have heard a lot about 802.16j Mobile Multihop Relay (MMR). Will you have a base station with MMR capability.

A: Yes, not only will we have this capability, we envision a future  software upgrade to enhance our existing base stations.

Q: I am a real "techie", are their any technical advantages of mobile 802.16e over fixed 802.16d?

A: Yes, there are advantages of mobile 16e over 16d fixed. Here is a partial list:

Scalable FFT: in 802.16e, the FFT size scales with bandwidth, improving efficiency. 802.16d has a fixed FFT size.

Subchannelization: 16e optionally offers special subchannelization which can provide marked improvements, especially in the UL. (OFDM/802.16d does offer subchannelization but far less complex)  When subchannelization is implemented, more transmit power can be allocated to a user with less favorable channel conditions within the same time slot, while lowering the power for users in better locations.
 

There is also a scheduling advantage with 802.16e subchannelization. In an OFDM/802.16d system, only one user can be scheduled per symbol as opposed to OFDMA/802.16e where multiple users can be scheduled per symbol.


Power Reduction: Though this is probably not hypercritical for WISPs, yet it  is an advantage. 16e introduced sleep and idle modes which reduce power when  the airlink is not being used. In sleep mode, the CPE "wakes up" to  periodically check in with the BS and remains in quasi-power down mode  otherwise. In idle mode, the CPE shuts down all functions to all but the  bare minimum and is activated when the CPE returns to activity. These modes  make a more efficient airlink and reduced electricity bills are always good  to have.
 

Additional QoS: 802.16e introduced "Extended Real-Time Polling Service" which  generates variable packet sizes specifically targeting VoIP applications.  ErtPS also improves jitter and latency for VoIP. So this will improve VoIP  performance for WISPs offering VoIP services.
 

 
   
 
 
 
   
 
 
 
   
 
 

Frequently Asked Questions

 
   
 
 

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