Connected Real Estate Magazine - Vol 1 Issue 2 - 48
THE REALITY BEHIND IN-BUILDING DAS COSTS
plug-and-play type RF devices from operators that can utilize pre-existing IP WAN connectivity in the building. And,
they are easier for neutral hosts and integrators to deploy, as
compared to a full base station deployment from an operator.
Small cell solutions have attempted to emulate a WiFi
access point look and deployment approach, creating smaller
ceiling mount devices that can use Category X POE cables
for example. On the surface, this sounds great. However, the
nature of WiFi RF operation is very different than cellular.
In reality, these WAP-like nodes cannot typically be deployed
by people without cellular expertise - despite the marketing
hype by some. The more challenging issue is that there is little
to no flexibility in the RF pattern planning because of the
single-minded nature of the internal antenna. They tend to
create significant areas of interference that must be mitigated
through additional adaptations. Then keep in mind that you
need to mount a separate ceiling device for each carrier, possibly creating even more interference issues. These solutions are
significantly more complicated than they are marketed.
In contrast, many do not like the idea of pulling coaxial
cables in what is called the "horizontals" (across the ceiling areas) to antennas for a DAS solution. These often require PIM
(passive intermodulation) testing to ensure performance of all
the connections. However, this process is well known among
many neutral hosts and integrators. They all own PIM testing
equipment already, whereas a CAT X cable and related BCSII
testing of these is a bit foreign to them.
"The fact is, in almost all cases you are pulling some cables
horizontally," said Landry. "For many, whether this is coaxial,
CAT, or even fiber, it is still a cable pull."
The other key difference to compare between a DAS and
a small cell solution is the interruption to tenants within a
building. Devices mounted within ceilings with a DAS are very
simple passive devices. No power has to be run to them and
they are not "active" electronics - so the likelihood of servicing
them is virtually non-existent. In the DAS topology, all active
equipment is maintained within the technical room or the IDF
(Intermediate Distribution Frame) that is accessible without
interruption of the tenant. Add to this the fact that these single
antennas can host all the mobile operators and all their bands, in
a clean, simple, and more aesthetically appealing look.
That said, not all DAS equipment is the same. Many do not
control their own technology and have not integrated the many
optimizations for an E-DAS solution like JMA Wireless has.
Landry spelled out several differentiators that JMA
Wireless brings to this market. The first is efficient and fully
integrated product technology that streamlines deployments
48 CONNECTED REAL ESTATE | FALL 2017