As many people worldwide are still getting used to, benefiting from the improvements, and confronting the shortcomings of 5G cellular, standards organizations and industry cooperatives are busy preparing for 6G. This next-generation communications network will add sensing to its capabilities. Called integrated sensing and communication (ISAC) or joint communications and sensing (JCAS), the addition of sensing to communications will improve or enable numerous use cases.
The idea is that radio frequency-based sensor technologies, such as radar, can be integrated into radio communications transmissions and significantly improve and benefit the infrastructure and the applications. In addition to the automotive industry, which has an obvious need for both radar sensing and communication in autonomous vehicles, new use cases will expand in data communication and environmental sensing for surveillance, telemedicine/ehealth, industrial, and drone applications. Unlike previous approaches, with ISAC, the mobile network itself will act as a sensor.
Existing ISAC/JCAS activities
With the increased complexity of sensing and communications, several global cooperatives and standards organizations are examining how best to accomplish their goals.
For example, the European Telecommunications Standards Institute or ETSI has an Industry Specification Group (ISG) for ISAC. Among ts activities is the definition of a prioritized set of 6G use cases and sensing types with a roadmap for their study and evaluation. They e also studying the privacy and security aspects of sensing data.
Another European Consortium, the KomSens 6G project, is developing a new system architecture and investigating two different application scenarios for using radar technology effectively in 6G networks. Monostatic radar measurements locate the transmitter and receiver together. In contrast, multi-static radar measurements employ distributed transmitter and receiver units.
In North America, the Alliance for Telecommunications Industry Solutions (ATIS), a technology and solutions development organization, has the Next G Alliance (NGA) initiative to advance North American wireless technology leadership over the next decade through private-sector-led efforts. In its 6G Technology Management and Orchestration report, NGA notes that 6G systems, by adding sensing, are expected to address a wider range of use cases and markets than previous generations.
The Institute of Electrical and Electronics Engineers (IEEE) has recently initiated an effort to develop IEEE 802.11bf for WLAN sensing. This revised specification will transform Wi-Fi devices into object sensors that perform enhanced sensing operations in frequency bands between 1 and 7.125 GHz and above 45 GHz.
Implementing ISAC
An ISAC system should be able to optimize spectrum utilization, enable hardware reuse, and reduce power consumption by using a single waveform to perform communication and radar functionalities simultaneously. Current JCAS systems design approaches can be classified into three categories: communication‐centric, radar‐centric, and joint design optimized.
Several aspects have been proposed or defined in all design concepts for a device’s participation in the sensing process. First is the sensing initiator, a station (STA) that triggers a WLAN sensing procedure and requests the sensing results. Next, the sensing responder, a non-initiator STA, participates/replies in the WLAN sensing procedure initiated by a sensing initiator. The ST sensing transmitter transmits packets used for sensing measurements. An STA sensing receiver receives packets sent by a sensing transmitter and performs sensing measurements. Finally, an STA sensing processor processes the sensing measurements and obtains the subsequent sensing results.
The ongoing industry efforts to integrate sensing with communications should provide some extremely interesting solutions.
References
Integrated Sensing and Communications
Integrating Sensing and Communications
Integrated sensing and communication (ISAC)
6G Technology Management and Orchestration
Introduction to Joint Communications and Sensing (JCAS)