[Starlink] On FiWi

[David Fernández]

Hi Bob,

If you want that FiWi infrastructure on buildings, I am afraid that
you only get it (in the long term) with a law that makes it mandatory
to make new buildings with that infrastructure for communications.

In Spain, it should be added to this:
https://avancedigital.mineco.gob.es/Infraestructuras/Paginas/Index.aspx

Regards,

David

> Date: Mon, 13 Mar 2023 21:27:23 -0700
> From: rjmcmahon <rjmcmahon at rjmcmahon.com>
> To: Sebastian Moeller <moeller0 at gmx.de>
> Cc: dan <dandenson at gmail.com>, Jeremy Austin <jeremy at aterlo.com>, Rpm
> 	<rpm at lists.bufferbloat.net>, libreqos
> 	<libreqos at lists.bufferbloat.net>, Dave Taht via Starlink
> 	<starlink at lists.bufferbloat.net>, bloat <bloat at lists.bufferbloat.net>
> Subject: [Starlink] On FiWi
> Message-ID: <bc1cfdf998bb6bb246a632f0dc0fe3a8 at rjmcmahon.com>
> Content-Type: text/plain; charset=UTF-8; format=flowed
>
> To change the topic - curious to thoughts on FiWi.
>
> Imagine a world with no copper cable called FiWi (Fiber,VCSEL/CMOS
> Radios, Antennas) and which is point to point inside a building
> connected to virtualized APs fiber hops away. Each remote radio head
> (RRH) would consume 5W or less and only when active. No need for things
> like zigbee, or meshes, or threads as each radio has a fiber connection
> via Corning's actifi or equivalent. Eliminate the AP/Client power
> imbalance. Plastics also can house smoke or other sensors.
>
> Some reminders from Paul Baran in 1994 (and from David Reed)
>
> o) Shorter range rf transceivers connected to fiber could produce a
> significant improvement - - tremendous improvement, really.
> o) a mixture of terrestrial links plus shorter range radio links has the
> effect of increasing by orders and orders of magnitude the amount of
> frequency spectrum that can be made available.
> o) By authorizing high power to support a few users to reach slightly
> longer distances we deprive ourselves of the opportunity to serve the
> many.
> o) Communications systems can be built with 10dB ratio
> o) Digital transmission when properly done allows a small signal to
> noise ratio to be used successfully to retrieve an error free signal.
> o) And, never forget, any transmission capacity not used is wasted
> forever, like water over the dam. Not using such techniques represent
> lost opportunity.
>
> And on waveguides:
>
> o) "Fiber transmission loss is ~0.5dB/km for single mode fiber,
> independent of modulation"
> o) “Copper cables and PCB traces are very frequency dependent.  At
> 100Gb/s, the loss is in dB/inch."
> o) "Free space: the power density of the radio waves decreases with the
> square of distance from the transmitting antenna due to spreading of the
> electromagnetic energy in space according to the inverse square law"
>
> The sunk costs & long-lived parts of FiWi are the fiber and the CPE
> plastics & antennas, as CMOS radios+ & fiber/laser, e.g. VCSEL could be
> pluggable, allowing for field upgrades. Just like swapping out SFP in a
> data center.
>
> This approach basically drives out WiFi latency by eliminating shared
> queues and increases capacity by orders of magnitude by leveraging 10dB
> in the spatial dimension, all of which is achieved by a physical design.
> Just place enough RRHs as needed (similar to a pop up sprinkler in an
> irrigation system.)
>
> Start and build this for an MDU and the value of the building improves.
> Sadly, there seems no way to capture that value other than over long
> term use. It doesn't matter whether the leader of the HOA tries to
> capture the value or if a last mile provider tries. The value remains
> sunk or hidden with nothing on the asset side of the balance sheet.
> We've got a CAPEX spend that has to be made up via "OPEX returns" over
> years.
>
> But the asset is there.
>
> How do we do this?
>
> Bob
>