Group,
Has anyone deployed a hop of the 5.4 GHz PTP Series equipment?
I am in the process of deploying a NLOS hop that is about 1.5 miles long. At approximately 1.3 miles into the path there is a group of trees prohibiting LOS.
We have deployed 5.8 GHz PTP Series equipment in the past which has performed extremely well in NLOS conditions.
For this particular 5.4 GHz hop, the MASTER side would be collocated with an existing 5.8 GHz PTP Series station. This is one of the reasons why I would like this new link we are working on a 5.4 GHz hop. The stations would most likely be collocated on the same mast. This is not a tower site, it is a rooftop. I would prefer to use the same mast, but if necessary, I can add a new non-penetrating roof mount specifically for the 5.4 GHz station.
My specific question is with regards to Tx Output power, antenna gain, and the FCC EIRP limitation in the 5.4 GHz band, specifically in a NLOS condition. With the version of firmware I am used to seeing in the 5.8 GHz PTP series radios, the units employ adaptive modulation to the point where the radios will automatically attenuate their transmitters to the lowest possible level in order to maintain the highest and most reliable order of modulation, and in-turn, data throughput. To my knowledge, there is no EIRP limit in the 5.8 GHz band for Point To Point applications. I understand the adaptive modulation technology, but I would still prefer the option to be able to manually set my Tx output power.
So with this in mind, with a 5.4 GHz NLOS link, is the firmware still the same such that it will dynamically adjust Tx Output power? If this is the case, I may need to start at the PTP500 or PTP600 series level in order to achive the customer’s throughput goal, based on some of the predicted loss I will incur through the foliage in the path.
Thoughts, suggestions, comments? Thanks in advance for your help.
there is an eirp limit on ptp 5.7ghz equipment which is 58db. unfortunately it is not anywhere close to that for 5.4ghz which is 30db. unknown to most people you can get a license to key gain full power on 5.4 but you do this at your own risk. if the fcc ever comes knockin they will definitely have you turn it down or off.
So what is the uppper limit for the “Maximum Output Power” of a 5.4 GHz PTP unit?
If the maximum value is consistent with the 5.8 GHz gear, it is 25 dBm.
Does that mean that in theory, we can only attach directional antenna with up to 5 dBi of gain without attenuating the transmitter?
If we are talking OFDM PTP (300/400/500/600) then the max transmit power on my integrated PTP400 unit is 4db.
Yes, we are talking OFDM PTP Series equipment.
If your max Tx power on the integrated antenna unit is 4 dBm, then the gain of the internal antenna must be 26 dBm.
Correction, the gain of the internal antenna must be 26 dBi, not dBm.
Has anyone deployed a hop of the PTP series 5.4 GHz equipment using the connectorized version of the radio?
If so, what is your range of values you can enter for the “Maximum Transmit Power” field?
Thanks,
Matt
That might help get you in the right direction. I don't have any connectorized units to look at to give you the values, but the above would be a good starting point.
Thanks for the reply and the link.
I have some e-mails into PTP Support regarding my questions also.
I took a look at the link, and I am still a bit confused, but hopefully Moto will be able to clear up the confusion.
We’ll see…
connectorized units are set to a max of 7db tx power, with 30db being max eirp. you can get a region 7 license that enables full 25db tx power although with anything more than a 5db antenna you would be above fcc regulation for 5.4ghz
Thank you. This is exactly the information I was looking for.
How do you go about getting one of those licenses?
goto their website http://motorola.motowi4solutions.com/support/ptp/licensekey.php and enter the info and they will email you a new license key. i would choose region 7 instead of 8 just because of the fact that it does DFS