Positioning LTE Direct against other proximity-aware technologies

LTE Direct, now being standardized in 3GPP as part of Release 12, is a platform for directly discovering and connecting nearby peers. Qualcomm and Samsung sponsored an LTE Direct workshop earlier this year in which several major operators participated. A few days ago Qualcomm made available a white paper, prepared jointly by some of the participants, that summarizes key points from the workshop.

Business opportunities are seen in social networking and retail, with one scenario being a store using LTE Direct to attract nearby foot traffic. There are other ways to use wireless to do this, but the paper positions LTE Direct as unique in terms of both radio capability and location privacy.

The paper divides existing proximity-aware communications technologies into two groups: peer-to-peer (P2P) and over-the-top (OTT). P2P solutions include Wi-Fi Direct and Bluetooth, and the paper finds fault with both:

Wi-Fi Direct provides device-to-device connectivity, and while it is possible to enable proximate discovery on Wi-Fi Direct in very low densities (<10 users), the battery impact increases exponentially as the number of users increases. This is primarily because Wi-Fi Direct is a two-step discovery process, operates in unlicensed spectrum, and deals with uncontrolled interference from other devices using the same spectrum. The range of Wi-Fi Direct (<100 meters) is also much lower than LTE Direct (up-to 500 meters).

Bluetooth also suffers from scalability issues similar to Wi-Fi Direct because it operates in unlicensed spectrum and also has a much lower range (tens of meters).

 OTT solutions are seen as coming under greater regulatory and other scrutiny over location privacy:

Most current location-based loyalty or retail apps require constant (or nearly constant) real-time location tracking through approximate, network-based, location and/or precise GPS location. The user can be located in a different city, across the country, or at his/her house, yet the retailer is constantly receiving location information. In contrast, with LTE Direct, a developer can create an app that broadcasts offers only to users near relevant merchants.

Wi-Fi Direct and Bluetooth can do that too, but the whole LTE Direct package, including better radio performance, is seen as a superior offering.

The paper also discusses interoperability and operator business-model issues.