Cellular-based 5G V2X latency measurements in vehicular environments have been successfully conducted by Rohde & Schwarz and Huawei in field tests in Munich and Shanghai. The initial measurements have shown that it is possible to achieve delays in the millisecond regime in a 5G network, demonstrating a superior latency performance in comparison to LTE.
One of the key use cases of 5G is ultra-reliable low-latency communication (URLLC). Important for advanced vehicle-to-X communication use cases, URLLC will enable automated driving in the future.
In a joint project between Huawei and Rohde & Schwarz, a precision end-to-end delay measurement system for over-the-air IP transmissions was applied to 5G V2X communication for cooperative driving applications in field tests in a moving car.
A measurement accuracy below 2µs for each transmitted IP packet was demonstrated. The transmitted data contained various IP traffic streams including video, LIDAR and control data (ITS messages) for a tele-operated vehicle.
The precision absolute time standards on both ends were derived from two independent GPS receivers.
While the trial in Munich was related to a tele-operated driving project, the tests in Shanghai were related to a platoon V2X testing site, where a number of vehicles traveling together are electronically connected via wireless communication.
The delay for transmission of one IP packet from source over-the-air to a (moving) receiver (sink) needs to be measured, spanning all delays introduced by the radio transmitter, propagation delay and radio receiver from/to IP packet level.
As latency is one of the key performance indicators of 5G and crucial for safety applications, such measurements could become an important criterion for future certification testing.
Andreas Pauly, Executive Vice President Test & Measurement at Rohde & Schwarz, said: "We are delighted to collaborate with Huawei to contribute with our test and measurement expertise to 5G technology development. With a strong global footprint in the telco ecosystem and close cooperation with partners, Rohde & Schwarz is committed to further expanding our innovative test and measurement solutions to new automotive applications."