Small cells have become a pretty important tool for wireless carriers to use in their networks. It allows them to add more bandwidth in densely populated areas, which is important in this day and age with so many smartphones and other tech gadgets on these wireless networks. According to a survey out of IHS, 90% of the world's wireless carriers have deployed small cells. On top of that, the 10% that haven't yet deployed them, plan to do so by the end of next year. Here in the US, Verizon, Sprint and AT&T have deployed small cells. Mostly in downtown areas, near arenas and even in shopping malls.
Why are so many carriers relying on small cells for their network? The biggest reason is security. IHS' survey says that about 90% cited that as a reason for using small cells. IHS continued by saying that "security has consistently risen from the bottom of respondents' lists five years ago to the top-rate feature this year after placing second last year." A big reason for this is due to the number of security breaches and network hacking that has been taking place in recent years.
IHS has also said that small cells is a great way for carriers to reduce churn (customers leaving versus customers coming to their network) as well as increase revenue. Which is something that carriers are always going to be interested in, for obvious reasons. Small cells are typically deployed between 1.5GHz and 2.2GHz spectrum, which is where 3G and LTE networks are typically. That's important because, for the most part, users are only using either 3G or LTE, with the preference being on LTE right now.
Small cells are likely all around your city, they are typically on utility poles, although some companies have gotten pretty innovative as to where to install them. With Philips including them in their smart light poles that they are shopping around to cities that want to turn their city into a "smart city". The good thing about Philips doing this, is the fact that their small cells actually works with all of the US carriers, unlike when Verizon deploys a small cell, it only benefits their own customers. Small cells are not always visible, but they are definitely helpful.