Device-to-device (D2D) communication refers to the technology that allows user equipment (UE) devices to communicate with each other with or without the involvement of network infrastructures such as an access point or base stations. D2D is promising because it makes ultra-low latency communication possible. But who is using D2D and what are the real applications behind this technology? In this white paper, learn about D2D and how it enables fifth generation (5G) wireless network communication from short-range wireless to vehicle-to-vehicle communications
What Is D2D?
D2D enables the communication between devices such as cell phones or vehicles. This technique enables new device-centric communication that doesn’t require direct communication with the network infrastructure. Thus, it is expected to solve part of the network capacity issue as 5G promises to connect more devices in faster, more reliable networks.
Dedicated short-range communications (DSRC) technology is often tied to 802.11p, which is the Wi-Fi standard specific to the automotive industry that leads the next generation of connected cars. In a February 15 news release, Volkswagen announced that it will provide
WLANp as standard equipment on all its cars in Europe starting in 2019. This announcement could create ripple effects in the industry to promote accident-free driving and, ultimately, autonomous driving.
However, the challenge with 802.11p technology is that it works only with cars that can transceive its protocol. Though 802.11p technology communicates safety-related information for driving such as what the weather is like at the end of a tunnel, it works only with cars that can transceive its protocol. To support complete autonomous driving, communication via cellular networks is essential. This new area is called C-V2X, where “X” is “everything” such as another car (V2V), pedestrians (V2P), networks (V2N), and so on. In this white paper, C-V2X mainly refers to LTE-V2X.
C-V2X delivers the major benefit of using the existing LTE network infrastructure, according to the initial V2V standard completion announcement by 3GPP in September 2016. It promotes high data rates, high coverage, lower latency with 5G, and more. Based on these great expectations, virtually every automotive company is looking at C-V2X as the next “it” technology that will pave the path to completely autonomous driving.
Consider the following scenario.
A major challenge of C-V2X is that it has yet to be tested or validated unlike 802.11p, which was standardized over 10 years ago. According to a September 2017 white paper published by Autotalks and NXP, Phase 2 of the C-V2X standardization is expected to be introduced in December 2018 and will cover the following topics:
■ Carrier aggregation (up to eight PC5 carriers)
■ Gain and feasibility of shortened TTI (<1 ms)
■ Gain and feasibility of transmit diversity
What’s Ahead for Us
Whether D2D communication is developed with or without the network infrastructure in mind, it will help connect more devices with boosted data rates and reduced latency. D2D may be one of the essential technologies to meet 5G wireless network challenges in many industries. However, other technologies such as LIDAR, radar, cameras, the network to connect all, the brain to control, etc., must be tested and ensured everything works in sync without failure until the arrival of true autonomous driving, defined as Level 5 by SAE International, which some say will take another five to 10 years.
The good news is we are definitely moving in the right direction. The automobile industry has implemented some truly impressive advancements. Tesla, for example, has announced cars on tesla.com/autopilot with hardware capable of full self-driving. They automatically search for parking spaces and park themselves after the driver and passengers step out of the car.
The trepidation some parents feel when they send their 16-year-old to drive on the road for the first time may soon come to an end. However, as the standards are finalized, more development and prototyping are needed, some of which the cellular community and automotive industry are already addressing.