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That is but one new way the FCC
believes spectrum access in the
mobile and other industries should
become “virtualized,” in the sense that
devices and services can use physical
assets “across networks,” with less
constraint based on the “ownership” of
access assets.
That is the access network’s ver-
sion of the broader virtualization of
services and apps from physical layer
networks.
In some ways, in addition to virtu-
alization, device access also is being
“converged” (integrated) more directly
than in the recent past, when smart-
phones have universally acquired the
ability to connect to Wi-Fi.
A better illustration of how access
virtualization will work in the future
is the way Google Fi uses any one
of three networks to provide smart-
phone access: Wi-Fi or the Sprint
network or the T-Mobile U.S. network,
whichever provides the best signal at
a particular moment.
Another example of the coming
virtualization of access: the FCC has
authorized spectrum sharing between
licensed spectrum holders and other
commercial entities in the 3.5 GHz
band. The Citizens Broadband Radio
Service (CBRS) creates a three-tier
licensing approach. Though the actual
license holder (a government entity)
retains priority access to the spectrum
when it is needed, secondary licenses
can be created for areas where there
Virtualization is the next wave
for networks, both core and access
Open
Access
By
Gary
Kim
T
he Federal Communications Commission in
February 2017 authorized a new air interface
and access protocol called LTE-U (Long Term
Evolution-Unlicensed).
is surplus capacity, or the capacity
actually is not being used at all.
Where capacity remains even
after the primary and secondary li-
censees are concerned, the surplus
can be used on a best-effort basis by
devices (on the Wi-Fi pattern).
There also are new protocols that
allow entities to create 4G mobile
networks using only unlicensed spec-
trum, such as Qualcomm’s MulteFire.
In such cases, 5G networks might be
CBRS Introduces a 3-Tiered Shared Spectrum
Source: Qualcomm
Opens up 150 MHz spectrum while incumbents are still using it
Incumbents are protected
from interference from
PAL and GAA
Tier 1
Incumbents
Tier 2
Priority Acces
Licenses (PAL)
Tier 3
General Authorized
Access (GAA)
PAL has priority over GAA
licensed via auction, 10 MHz
blocks, up to 7 licenses
GAA can use any spectrum
not used, yields to PAL and
incumbents
3550
3600
3650
3700 MHz
Navy radar
FSS RX
WISPs
PAL
GAA
Virtual Realities
Channel
Vision
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March - April, 2017
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