Bringing fifth generation wireless to mobile

If you have a smartphone you know that when you are not using Wi-Fi, you are using mobile data. Fourth generation wireless (4G) and Long-Term Evolution (LTE) are the most common symbols you see when using mobile data, however the current demand on mobile data traffic has far exceeded what 4G and LTE wireless can support. Fifth generation wireless (5G) looks to be a promising solution to the need for higher data capacity, but it has yet to be used for mobile wireless communication.

Dr. Kamran Entesari, professor in the Department of Electrical and Computer Engineering at Texas A&M University, is working to address concerns associated with bringing 5G to mobile and offering solutions.

One of the most effective solutions to handle the high data capacity for 5G is to utilize the millimeter wave spectrum (mm-wave), which is between 30 and 300 gigahertz.

Because of the high cost of components and the high rate of radio signal broadcast loss in air, 5G frequencies have mostly been utilized for applications such as indoor high-resolution multimedia streaming, but not for mobile communication.

“To be able to utilize the mm-wave spectrum for cellular connectivity, the issues of sufficiently large coverage and supporting mobility need to be properly addressed,” Entesari said.

Entesari’s focus is to allow radios to support beamforming antennas for 5G mobile users in both transmit and receive modes. Beamforming is a signal processing technique that transmits a signal directly to the receiver, which creates a stronger and more reliable wireless communication.

For each antenna element, a radio unit is required. Each radio unit includes a transmitter to send the radio signal from the mobile unit to the base station through the antenna and a receiver to collect the incoming radio signal from the base station.

In the initial version, the transmitter and receiver work at different time slots to assure their radio signals do not affect each other. However, in the more advanced version, the transmitter and receiver are supposed to work simultaneously to increase mobile data capacity, but this is a very challenging problem since their radio signals directly interact with each other. Entesari is working to address this issue by finding a way to effectively cancel the leaked signal to the receiver using a replica of the main transmitted signal.

This research will directly impact the quality of mobile connectivity and enable a new way to support the ever-increasing mobile data traffic for media such as live streaming, social media, ultra-high definition and 3D video content.

This work is sponsored by Qualcomm Inc., who has awarded this project a university grant and presented Entesari with the Qualcomm faculty award.