Your smart phone and other electronic devices in your home, use very specific frequencies on the radio frequency spectrum. Typically, those under 6GHz, but these frequencies are starting to get more crowded. Carriers can only squeeze so many bits of data on the same amount of radio frequency spectrum. As more devices come online, we're going to start to see lower service and more dropped connections. The solution is to open up some new real estate. The researchers are experimenting with broadcasting on shorter millimeter waves, those that fall between 30 and 300 GHz. This section of spectrum has never been used before for mobile devices, and opening it up means more bandwidth for everyone.

Here is an example of how beamforming works: image that you are in a cluster of buildings and you are trying to make a phone call, and your signal is ricocheting off of surrounding buildings and cries-crossing with other signals from users in the area. A massive MIMO base station receives all of these signals and keeps track of the timing and the direction of their arrival, the uses signal processing algorithms to triangulate exactly where each signal is coming from and plots the best transmission route back through the air to each phone. Sometimes, it will bounce individual packets of data in different directions off of buildings or other objects to keep signals from interfering with each other, and the result is a coherent data stream sent only to you.

Today’s cellular base stations have exact same hold up a basic antenna can only do one job at a time, either transmit or receive. This is because of a principle called reciprocity which is the tendency for radio waves to travel both forward and backward along the same frequency. To understand this, it helps to think of a wave like a train loaded up with data: the frequency it’s traveling on is like the train track, and if there is a second train trying to go in the opposite direction on the same track, people need to get some interference. Up until now, the solution has been to have the trains take turns or to put all the trains on different tracks or frequencies, but people can make things more efficient by working around reciprocity. Researchers have used silicon transistors to create high speed switches that halt the backward of these waves, and it is kind of signaling system that can momentarily reroute to train so they can get pass each other, that means there is more getting done on each track a whole lot faster.