Cell Phones Get Sly

Cell Phones Get Sly

Electrical and Computer Engineering | Faculty of Applied Science
Share Story Related Content Add to my report

It seems that almost everyone in the world has a cell phone or ‘smart device’ to stay in touch with everyone else.

But when something big happens in that world, such as a gas explosion, wild Stanley Cup final or similar localized ‘disaster’, almost everyone will reach for that mobile phone, all at once and repeatedly.

The result: tsunamis of colliding texts, firestorms of bandwidth overload, coming in all at once from all sides. When hit too hard, cellular networks overload: frequency gridlock.

For emergency responders who rely on wireless communications – and for the disaster victims whose very lives depend upon a speedy, coordinated rescue – overloaded cellular networks are very bad news. Even a single dropped call can have big consequences.

With the standard frequencies jammed, the first responders can only wait, frustrated, their own crucial calls fighting to get through the tangle. So why not sidestep the crowded frequencies and take a different – and far broader – route?

Mai Hassan has done exactly that. The PhD candidate in the UBC Department of Electrical and Computer Engineering has discovered a reliable way for cellular signals to ‘piggy back’ aboard the wider spectrum of local television and radio channels – even when those channels are active – and not only get the crucial messages safely and quickly to their destinations but do so without disturbing the ‘borrowed’ carrier signals.

Keeping the TV or radio receivers unaffected means controlling or ‘steering’ the direction of cellular transmissions; Hassan knew that if a wireless device is fitted with an array of internal antennas, such control is possible – but it wouldn’t be cheap.

To achieve a more “cost-efficient solution” she first considered the “cooperation between multiple nearby cell phones, each with its own antenna but together forming “a virtual array of antennas” that can give the same effect of direction control: “Yet this solution had its own challenges. For example, the need to synchronize the cooperative transmission from different cell phones.”

Without getting too technical, Hassan discovered how to ‘shape’ the wireless signal and via a cellphone’s ‘smart’ antennas, select, separate and steer the transmission through the clutter, aligning it neatly with – and unobtrusively aboard – the radio and TV bandwidths. As well, the manipulated signal’s ‘constructive interference’ actually reinforces the signal, turning a potential obstacle into a strong and long-distance strength.

Hassan’s ingenious ‘fix’ has been published in the journal IEEE Transactions on Wireless Communications; the research was supervised by Assistant Professor Jahangir Hossain in the School of Engineering on UBC’s Okanagan campus and Professor Vijay Bhargava in the Department of Electrical and Computer Engineering on UBC’s Vancouver campus.

Read more about

Research Excellence

Related Content

Mai Hassan has found a way to prevent dropped calls in an emergency. Photo credit: Martin Dee
Hassan’s ingenious ‘fix’ has been published in the journal IEEE Transactions on Wireless Communications. Photo credit: Martin Dee

Campus

Okanagan

Campus

Vancouver

"For emergency responders who rely on wireless communications, overloaded cellular networks are very bad news. Even a single dropped call can have big consequences."

Twitter

Congratulations Nabil Shalabi, Kyle Searles, and Kenichi Takahata who have recently had their article “Switch Mode… https://t.co/VXjvRMwqMT
1 day ago.
Looking for a quiet space on campus to meditate, reflect, or pray? Browse through https://t .co/Pj8qxIRV6T for avail… https://t.co/puJ8beeKL2
3 days ago.
We are happy to announce that Dr. Rabab Ward, professor emeritus in the ECE Department, has been elected as Vice Pr… https://t.co/K9ZPwh4IJh
20 Jan, 23
Yasaman Gharib graduated from the Department of Electrical and Computer Engineering at UBC in November 2012. Read… https://t.co/bR2TSIuKXv
18 Jan, 23
With term 2 underway, you may be wondering about available resources to address and manage stress, anxiety, and you… https://t.co/1wDVtVe9oC
16 Jan, 23
Welcome back to all of our ECE students, faculty and staff! We look forward to working with you in 2023! Check ou… https://t.co/L4zaRI8Mcf
10 Jan, 23
Rui Xi is a current PhD student at ECE UBC. Rui developed GoHigh, a fully-automated tool that replaces low-level fu… https://t.co/tbl9rpik5E
12 Dec, 22
“If we can get rid of all the unnecessary middlemen and come up with models to help people monetize their data, the… https://t.co/cL1a7CEUXG
1 Dec, 22
The Department of Electrical and Computer Engineering is currently looking to hire an assistant or associate profes… https://t.co/3oujQaCJlF
22 Nov, 22
The Department of Electrical and Computer Engineering is currently looking to hire an assistant, associate, or full… https://t.co/iV3HJXK19u
21 Nov, 22

Leave a Reply