There are three types of communication technologies which are used for the development of autonomous vehicles: DSRC, C-V2X and Hybrid V2X.

DSRC

DSRC (dedicated short-range communication) is the type of communication technology that is used for wireless communication in vehicles. As the name suggests, this technology is more effective for short-range communication. DSRC is allocated with 75 MHz spectrum in 5.9 GHz band, which can enable vehicles to communicate with each other over short distances.

DSRC is less prone to interference in communication, even in bad weather conditions. It has high reliability and low latency. It is also considered secure due to its short range. In DSRC, on-board units (OBUs) in vehicles are used for communication between vehicles. While for communication with infrastructure, the roadside units (RSUs) are used to alert drivers in case of any emergency.

DSRC is still the dominant technology for connected vehicles. In the US, federal authorities recommend using DSRC for vehicle communication. Auto companies are working on DSRC developments. Cadillac commercialised its Cadillac CTS sedan in 2017, which was equipped with DSRC technology. The US transportation department proposed to make DSRC technology compulsory part in future cars. 

C-V2X

C-V2X (cellular vehicle to everything communication) is also a type of communication, that use 4G LTE or 5G network for vehicles communications. By using the cellular network as a source of communication, C-V2X has the ability to communicate within long distances.

C-V2X operates in two modes. One is direct communication using the PC5 interface on 5.9 GHz band, which is allocated for vehicle communication. The first mode is aligned closely with DSRC and can warn the driver about any short-range situations. The other method is communication over the regular licensed cellular band. It has the ability to handle situations such as long-range road and traffic conditions, and also handle the communication of vehicles with a cloud.

Qualcomm is more focused on C-V2X development and deployment. Qualcomm is a chipmaker and is making C-V2X chips since 2018. Ford, an automaker, is trying to use C-V2X in its vehicles instead of DSRC, as forced by various regulators. Ford announced that its C-V2X technology would be equipped in all of its new US models, from 2022.

Hybrid V2X

As the name suggests, hybrid V2X is a type of vehicle communication technology which has the ability to use both DSRC and C-V2X, at the same time. It uses DSRC for short-range communication while C-V2X for long-range.

It makes more efficient and also has the advantage to be used across the globe as it can be adopted as per the regional requirement of either DSRC or C-V2X. It can also help vehicle manufacturers who are worried regarding making selection between C-V2X and DSRC.

Continental AG and HARMAN International (a wholly-owned subsidiary of Samsung Electronics Co., Ltd.,) announced to provide the hybrid C-V2X solution for automakers. Autotalks (an Israeli start-up) announced the launch of its Vehicle-to-Everything (V2X) chipset that is capable of supporting both dedicated short-range communications (DSRC) and C-V2X based on 3GPP specifications.