airMAX - General FAQ

Overview


This article answers some of the most common questions about airMAX. Use the table of contents below to navigate to the questions that interest you.

message_outline_light.png  This article will be updated as more common questions are brought to our attention. If you feel that a question is missing, please click the feedback button at the bottom of this page and let us know!

Table of Contents


1. What is airMAX priority?

2. Is there any benefit to using Rocket5AC Prism with Non-Prism Sector antenna and then nanobeam AC as CPE?

3. What is the difference between Router and SOHO Router mode?

4. What are the maximum numbers of clients that can connect to M and AC Access Points?

5. What radios support UNII1, UNII2 and UNII3 bands?

 6. What is the range of airMAX devices? 

7. What are the differences in performance for 20MHz and 40MHz channel width and when to set it?

8. What is airSelect?

9. What is the best signal strength and noise floor?

10. Why would I use the IsoStation or PrismStation?

11. What is airPRISM?

12. Low CCQ; what is it and how to I make it better?

13. What is Enhanced TX Modeling?

 


1. What is airMAX priority?


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Most consumers will leave this set to base for all CPEs. Here is an article to explain what this feature does.


2. Is there any benefit to using Rocket5AC Prism with Non-Prism Sector antenna and then nanobeam AC as CPE?


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Yes! Prism technology filters interference out at the device itself. Most interference in the WISP industry is seen at AP level because it can “see” so many other devices with its wide beam-width. This issue isn’t as common at the CPE because they are normally lower to the ground with a much tighter beam-width.


3. What is the difference between Router and SOHO Router mode?


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  • In Router Mode, the WAN interface is the wireless interface, and the Local LAN interface is the Ethernet port.
  • In SOHO Router mode, this is reversed so that the WAN interface is the Ethernet port and the Local LAN is the Wireless interface.

4. What are the maximum numbers of clients that can connect to M and AC Access Points?


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  • M:  127
  • AC: 85
  • AC with GPS Sync enabled: 60
info_i_25x25.png Note: Even though the hardware allows these high numbers of clients, that does not mean that you should plan on connecting that many clients to one Access Point. The maximum capacity of an AP is determined by channel width, signal, and noise. Any PTMP product is based on the assumption that not all clients require maximum capacity at the same time.

5. What radios support UNII1, UNII2 and UNII3 bands?


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All of our 5Ghz devices support UNII1, UNII2, and UNII3. Your country’s laws and regulations will either allow or disallow you to uses these bands.

info_i_25x25.png Note: In the United States, the FCC controls these rules. Due to changes in regulation, we provide unlock codes to be applied with updated firmware to enable these bands. So, if you see that you can’t use these bands, upgrade your firmware and check the System Tab of your device. If you see the Activate UNII Rules button, you need to apply for the code here: FCC Label Request

6. What is the range of airMAX devices?


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The range of airMAX devices can vary greatly. To know what device you should use for your installation, you should always use our Link Calculator which can be found at airlink.ubnt.com


7. What are the differences in performance for 20MHz and 40MHz channel width and when to set it?


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  • You always want to use the smallest channel width possible.
  • The wider your channel width, the larger your spectrum footprint is. 40MHz can cause self-interference and is the most vulnerable to interference from other wireless radios, but it can provide greater throughput than 20MHZ.
  • 20MHz commonly provides enough throughput without being affecting by as much outside interference or causing interference with other radios.

8. What is airSelect?


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To use airSelect, the user selects a list of frequencies, and the AP will cycle through each selected frequency in order to avoid interference. It records the noise floor of each frequency and spends more time on the best frequency. This feature is only used in very uncommon situations and is rarely recommended to most consumers.


9. What is the best signal strength and noise floor?


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  • You want your signal to always be between a -45 and -65 dBm.
  • Signals that are “too hot” -40dBm or greater can increase EVM and reduce performance.  These should be indicated in red on the APs Station List (AC)
  • The way to decide what signals you need is to look at the Signal to Noise Ratio, also known as SNR. For best performance, we recommend an SNR of at least 25 but preferably 30 or greater. So, if you have a noise floor of -90 dB, you will need to have at least a -65 signal.

10. Why would I use the IsoStation or PrismStation?


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Both the IsoStation and the PrismStation have four different antenna options.

  • Asymmetrical 90°
  • Asymmetrical 60°
  • Symmetrical 45°
  • Symmetrical 30

Signal range is up to 5+ km (3+ miles) for both.

The only difference between the two is the PrismStation has airPrism and GPS for better co-location. The IsoStation is a less expensive alternative for deployments that do not need as much isolation.

Asymmetrical horn antenna options (60° and 90°) have naturally attenuated side lobes and extremely low back radiation, and they offer industry-leading front-to-back ratio and low side lobe radiation. Symmetrical horn antennas (30° and 45°) are ideal for cluster sector installations with high co-location requirements.


11. What is airPRISM?


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airPrism technology isolates signals within the operating channel to increase capacity and throughput in co-location deployments.

For a much more in-depth explanation check out this Blog from Robert himself.


12. Low CCQ; what is it and how to I make it better?


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Low CCQ is a direct indicator of lost packets which might be due to the fact that there might be interference. Here are some suggestions to improve it:

  • Make sure that the units are properly aligned.
  • Check for noise in the area and select the channels accordingly
  • If there is a lot of noise, consider reducing the channel width of change the channel
  • Make sure that you have a clear line of sight
  • Make sure that the distance is set to auto (Advance Tab)

 

13. What is Enhanced TX Modeling?


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Advanced TX modeling models the effects of TX induced EVM limitations often due to excessive TX power. 

By default, airLink takes the numbers you input and shows you the theoretical capacities. But, due to the EVM(Error Vector Magnitude), you may be overdriving the conducted power. So, Enhanced TX Modeling takes the EVM into consideration and gives you a more literal link capacity.