The short burst concept could work. In that case, longer links would be
better. How many bits(bytes) can you fit into a microsecond? At 10
miles, transit time is a little over 53 microseconds. So both ends could
start transmitting at the same time, and if they shut up at 53
microseconds, the incoming would be in the clear.
bp
<part15sbs{at}gmail{dot}com>
On 5/4/2015 4:51 PM, Ken Hohhof wrote:
But if I try to talk while you're talking, on the assumption that by
the time you receive my transmission you will have stopped talking and
can now listen, I have the additional problem that I can't talk
because I'm listening.
The only way I see this working is if we send in extremely short
bursts no longer than the time the bits take to fly through the air.
So we both send our tiny burst, and just as the first bits get to the
other end, we both stop xmt and switch to rcv so we can grab the
bits. Modify this to allow for OFDM cyclic prefix and delays due to
multipath reflections, etc.
-----Original Message----- From: Bill Prince
Sent: Monday, May 04, 2015 6:42 PM
To: [email protected]
Subject: Re: [AFMUG] AF5 vs AF5X
Think of the air in between as a storage device.
bp
<part15sbs{at}gmail{dot}com>
On 5/4/2015 4:12 PM, Ken Hohhof wrote:
Ubiquiti claims to have that patent pending HDD mode where it figures
out how long the bits take to fly through the air.
I think of it as similar to road construction on one lane of a two
lane road, and somehow the flagger at one end will flip his sign from
STOP to SLOW before the guy at the other end. I can't wrap my head
around how that works.
-----Original Message----- From: George Skorup (Cyber Broadcasting)
Sent: Monday, May 04, 2015 6:03 PM
To: [email protected]
Subject: Re: [AFMUG] AF5 vs AF5X
I have one AF5 up running FDD in the DFS band at 3.4 miles. We didn't
want to try to push an AF24 that far. RTT average is around 0.8ms, so
yes, like a licensed radio.
No idea about the AF5X, haven't bought any. But I'd guess latency would
be similar to the AF5 or 24 in half-duplex mode, which is going to be
like 4-5ms. I have only done FDD though.. because it's moar better.
On 5/4/2015 5:53 PM, Ken Hohhof wrote:
So I assume latency in FDD mode is sub millisecond like a licensed
backhaul?
What's is latency like on the AF5X? Similar to a PTP600, a few
milliseconds and very constant?
-----Original Message----- From: George Skorup (Cyber Broadcasting)
Sent: Monday, May 04, 2015 5:48 PM
To: [email protected]
Subject: Re: [AFMUG] AF5 vs AF5X
No FDD. Not 48 volt. Not 40+ watts.
On 5/4/2015 5:45 PM, Ken Hohhof wrote:
Can someone point me to a concise explanation somewhere of the
difference between AF5 and AF5X? Where you would use each, and what
you give up with the X in return for smaller, cheaper, lower power,
and drop-in replacement for a Rocket?
I know it doesn't have the built-in high isolation TX and RX
antennas, and doesn't do a gig of throughput. But I'm sure there's
more to it. It's not jumping out at me on the UBNT website.
