As the standardization of 5G wireless networks progresses, the research community has started focusing on what 6G will be. Motivated by the need of ensuring high data-rates, while at the same time saving spectrum, a major technology that has been proposed for 6G is the integration of communication and sensing services in the same infrastructure. This is motivated by two main considerations:

1. 6G will have to employ higher carrier frequencies, above 60 GHz, in order to support the required data-rates and traffic volume, following the trend already initiated by 5G networks. However, this naturally pushes 6G networks towards frequency bands traditionally assigned to radar and sensing systems. In order not to waste spectrum, the integration of communication and sensing networks over the same frequency spectrum is inevitable.
2. 6G will have to be a perceptive network for a more efficient use of resources. Acquiring context information about the surrounding wireless scenario, e.g. the positions of users, the evolution of traffic demands and connectivity requests, enables to operate the network and schedule resources in a more efficient way, also providing new services like autonomous vehicles navigation, digital twinning, geolocation, digital health.

The integration between wireless communication networks and sensing systems has been already investigated for some years. However, so far the focus has been more on enabling the co-existence between the two systems on the same frequency spectrum, rather than implementing a true integration of the two functions in a single platform. Instead, major gains can be expected by taking a holistic approach in which one hardware platform transmits a single waveform that is designed to implement both information transmission and environment sensing at the same time. Serving such a vision, INTEGRATE aims at developing novel and holistic architectures for integrated communication and sensing.

To this end, INTEGRATE will leverage the technique of holographic beamforming by reconfigurable surfaces. Placing holographic surfaces inside a base station transceiver to provide beamforming capabilities to accommodate both the communication and sensing tasks, while at the same time keeping complexity and energy consumption at bay. Specifically, holographic beamforming promises two key advantages compared to traditional architectures.

1. Compared to existing hybrid MIMO architectures, it brings new degrees of freedom to the system, because the EM response of each RHS unit can be tuned and reconfigured in real time, in order for the whole RHS to exhibit a desired overall EM response. This can be exploited for example to focus the transmitted power in the direction of the intended receiver, and/or to minimize the interference towards non-intended receivers.
2. Compared to existing massive MIMO architectures, these new degrees of freedom come at a lower energy consumption and cost. RHSs are nearly-passive devices, only requiring a small amount of energy to power the hardware components that enable the reconfiguration (low-power switches like PIN diodes or varactors). Then, hundreds of units can be equipped on one RHS, in contrast to the dozens of antennas that are used in massive MIMO arrays. Moreover, the RHS operates in the analog domain, without requiring energy-consuming conversion to/from the digital domain.

In this context, the INTEGRATE project focuses on the theoretical, algorithmic, and architectural foundations of integrated communication and sensing networks, developing the first open access network-level simulator for joint communication and sensing. In particular, the INTEGRATE project will:

1. Develop reconfigurable holographic surfaces capable of supporting joint communication and sensing tasks and that can be integrated in wireless transceivers with minimal cost and energy requirements.
2. Characterize the fundamental performance limits of integrated communication and sensing networks, developing an algorithmic framework and protocol suite to approach these limits.
3. Build the first open access software simulation platform for joint communication and sensing networks.

In order to execute the research plan, the INTEGRATE project will hire 12 research fellows, who will work for the project beneficiaries, carrying out individual research plans that, together, will lead to the achievement of the project objectives. At the researcher level, the individual research plans and related job offers can be found here.

On a network level, at first, all activities to get INTEGRATE up and running will be performed, including the recruitment of the researchers, signature of the consortium agreement, and set-up of the project management bodies (e.g. supervisory board, recruitment committee). Next, all research and training activities start. All training, dissemination, exploitation, outreach, and any other project activity that requires the researchers input is executed. All researchers' individual projects will be completed and integrated.

The research activities comprise three main tasks:

• TASK 1 Engineering holographic surfaces: This task develops novel metasurface structures suitable to support joint communication and sensing. Novel models for holographic surfaces will be developed and green metasurfaces for joint communication and sensing will be engineered.
• Task 2 Transmission techniques and protocols: this task is focused on the design of joint communication and sensing networks. New fundamental performance limits will be derived, optimal waveform design and practical radio resource allocation for holographic-based integrated communication and sensing networks will be developed. Moreover, a novel software platform interface for automatic holographic surface control for joint communication and sensing network will be developed.
• Task 3 Network-level simulator: this task is focused on the development of a new ray tracing module for networks based on holographic surfaces as well as the development of protocols for automatic operation and management of joint communication and sensing networks. All techniques and protocols developed during the project will be integrated into an overall network-level simulator capable of emulating the behavior of large networks supporting integrated communication and sensing.