max range on 5.2 and 5.7

on the AP it has a config setting for the max milage. can the 5.2 or 5.7 go further than 15 miles? I have a person wanted service that is 16.33 miles away from a 5.2 and 5.7 cluster.

There is no limitation in the hardware of software that would stop you, it’s purely a free-space loss issue. You will probably need one of the 29dB Pac Wireless grid reflectors to get the gain for that long of a shot.

Just so that you are aware, setting the max distance further on your AP means that everyone on that AP will be affected.

I thought if the AP detects an SM trying to register that is further then the max distance, then it wont let it register.

I have had this issue when I have left the default setting and then been unable to register…

Right.

The question was if the 5.7’s could do more than 15 miles. They CAN if the FSP can be overcome. The max distance the radio can be set to is 30 miles.

this is a good question, although i want to keep going about what Jerry Richardson stated.

in what way will changing the max distance on the AP affect (effect) everyone?

Increasing the max range is essentially increasing the time the AP will wait. This means less data moved in a given time slice.

ahhh… for some reason I have been thinking that 15miles was the max distance you could set it… not that it matters as we never get a link more then 10 miles… (i don’t think we even try)…


yes increasing distance will decrease throughput… there is documentation for it… however, the AP has to make sure that it allocates enough guard time for the furthest SM to to receive/send.

I have followed the Motorola recommended guidelines for setting the Max Range on ALL AP’s in a cluster to approximately (longest link in cluster + 1) and I saw a decrese in my link tests. All link tests that were once a solid 100% in both directions decreased to roughly 95-98%.

I began incrementing the value up towards 15 until the link tests went back to 100%. The ultimate value I ended up at was 14.

we use 15… never played around with it…

VJ,

Setting max distance to 15 miles eats up another control slot - robbing a data slot per time slice, setting it back to 14, especially if you aren’t trying for anything over 10 miles anyway, will recoup that data slot for you.

Geroge thanks for that… .im writing a script as we speak… to conduct a match change…

out of curosity… how did you work that out

We have done a 20+ mile AP to SM link using a Sector antenna on the AP and Motodish on the other

VJ,

Came up during the Canopy training course. Since you only have a fixed number of slots per frame and the AP has to allow additional time for radios at the max distance to request service, one of the data slots is converted to a control slot allowing equal access for the furthest radios.

So we have a cluster with ~50 people on it and a max of 17 SM’s per AP…The max range is set to 22 miles as our longest shot is basically 20 miles. We have the control slot set to 1…should we adjust it?

No, the AP will add the slot if needed

Here are the results of different mileage settings in a 5.7 Advantage AP. To see the slot settings you have to click on Advanced Stats then click on Status again and scroll down to the bottom. (Assuming that the + sign indicates you may get an extra data slot if all the control slots are not being used, tech support chime in if I am wrong)


2 miles:

Data slots down 28+
Data slots up 9+

5 miles:

Data slots down 28+
Data slots up 9

10 miles:

Data slots down 27+
Data slots up 9

12 miles:

Data slots down 27+
Data slots up 8+ (this is what is shows, even though 14 miles gets you 9)

14 miles:

Data slots down 27
Data slots up 9

15 miles:

Data slots down 27
Data slots up 8+

20 miles:

Data slots down 26+
Data slots up 8+

22 miles:

Data slots down 26
Data slots up 8+

25 miles:

Data slots down 25+
Data slots up 8+

30 miles:

Data slots down 25
Data slots up 8

The control slot count will always show whatever you have it set to on the config page, it does not reflect the slots that are taken away from the data slots.

Bottom line is to set the max distance to your max customer, any extra could cost data slots resulting in decreased throughput.
Since all AP’s in a cluster should have the same distance settings the total loss for a cluster can be substantial.

When it comes to the control slot setting, there is a chart in the docs based on the number of users per AP.

The plus side to all this is that with the correct settings you can assure all your customers that their level of service is not distance dependent like some other services.