Ron
This message is only being sent to you. I do not want to destroy a productive
conversation with the usual suspects and FUD.
The presentation was a bit scary in one respect. I actually understood much of
the technical detail that was discussed.
;-)
I think the thing that struck me most was the importance of energy efficiency,
and the role that Massive MIMO will play in making cellular service more energy
efficient. At the same time, understanding how MIMO will be used to focus
energy to specific users seems to be very important to the provisioning of
fixed wireless broadband to homes as well.
So the real issue here seems to be related to how different spectrum
frequencies can be used to support data links over varying distances.
I have not been able to find any useful resources that tell us what the
coverage and capacity of a tower using Massive MIMO with 5G might be. Just
vague statements that 600 MHz is good for coverage while the mm bands are good
for capacity.
One aspect of the coverage issue is tower height, something broadcasters know a
lot about. As one travels the interstates we see a wide range of towers;
mostly low self supporting, but also many tall towers with traditional guy
wires.
Obviously taller towers may help with coverage using 600 MHz spectrum. What is
less clear is the power requirements for the shaped beams created via MIMO
antennas. I assume power must increase for the beams to work as the distance
increases.
So it would be helpful to understand just how large an area could be covered
from a tower using 600 MHz spectrum and what kind of bit rates could be
expected. You seem to fully understand these issues and are good with numbers,
so I am reaching out for your assistance and opinions.
There was one other comment in the presentation that I did not fully
understand. It involved the suitability of fiber to deal with the amount of
information needed to make 5G work. I do not know if the presenter was
referring to the dedicated fiber links from the base station to the MIMO
antennas, or the amount of data capacity needed to meet the delivery capacity
of the towers.
Other reports I have read recently talk about the relatively low data capacity
of earlier cellular standards leading up the 4G LTE. This allowed towers to be
interconnected with microwave links. It seems clear that 5G towers will need to
be connected to fiber, which is now widely available, especially along
Interstates and other major highway arteries.
So any useful feedback you could provide would be greatly appreciated.
Regards
Craig
On Aug 22, 2017, at 2:00 PM, Ron Economos <w6rz@xxxxxxxxxxx> wrote:
I also found this video from Rohde and Schwarz to be informative (not really
on
600 MHz, but 5G in general).
https://www.youtube.com/watch?v=nljwtkdHAYw
Ron
On 08/22/2017 06:43 AM, Craig Birkmaier wrote:
This slideshow from American Tower provides a ton of data, and insights
about the cellular industry. It tracks the history of each standard and the
deployment stages.
In essence each new technology is deployed first to provide "coverage," then
later investment turns to capacity. There are some interesting slides about
the current trends in the industry involving spectrum sharing to improve
capacity.
Beginning with slide 24 they get into the 5G story, with timelines on
spectrum availability, standardization, and availability of handsets and
tower gear. One interesting note is the effort required to start using MIMO
with LTE, which requires new antennas and cabling for each tower; this is a
necessary precursor to 5G deployment.
THen we get to several slides about 5G in the lower frequency bands,
including new deployments in the 600 MHz band. Turns out that to promote 5G
coverage, the lower frequencies are ideal - less data capacity, but much
better coverage AND the ability to penetrate buildings.
So there are really two 5G stories, one about distance/coverage, and the
other about micro deployments for capacity, INCLUDING fixed broadband.
ENJOY!
Regards
Craig
http://www.americantower.com/Assets/uploads/files/PDFs/investor-relations/2016/U.S.%20Technology%20Update%20and%205G%20Introduction.pdf
