5. Transformative Use Cases

Why ISAC Enables New Services

ISAC turns radio infrastructure into a sensing fabric. Instead of every device carrying expensive sensors, the network itself can help observe the environment and share useful information.

Each use case asks for something different: how finely targets must be separated, how fast they move, and how often the picture must refresh. Pick one in the lab below to see what it demands from the radio.

What does each use case ask of the radio?

1. Formula and symbols

$$B_{\rm required}=c/(2\Delta R)$$

$$T_{\rm required}=\lambda/(2\Delta v)$$

• $\Delta R$: desired monostatic range resolution
• $\Delta v$: desired radial-speed resolution
• $B$: required bandwidth
• $T$: required coherent observation time
• $\lambda$: carrier wavelength
• $c$: wave speed

Use case

V2X road safetyFactory robotsBreathing monitorDrone trackingGesture controlBeam management

2. Work with the current inputs

V2X road safety. Separate a cyclist from a car and track them at road speeds.

Band	Bandwidth enough?	Observation time λ/2Δv	Fits refresh?
3.5 GHz, 100 MHz	No	85.7 ms	No
28 GHz, 400 MHz	Yes	10.7 ms	Yes
140 GHz, 10 GHz	Yes	2.1 ms	Yes

3. Result

Range resolution50.0 cmneeds B ≥ 300 MHz

Speed resolution0.5 m/srefresh every 50 ms

First band that works28 GHz, 400 MHz

References for this section3

• F. Liu et al., "Integrated Sensing and Communications", IEEE JSAC, 2022.
• J. A. Zhang et al., "An Overview of Signal Processing Techniques for Joint Communication and Radar Sensing", IEEE JSTSP, 2021.
• Z. Yang et al., "RIS-Enabled ISAC: A Sensing-Assisted Communication Framework", Frontiers in Communications and Networks, 2023.

1. Autonomous Vehicles and V2X

ISAC base stations and roadside units can communicate with vehicles while sensing road users, obstacles, and motion. This can support:

• Collision warning.
• Cooperative perception.
• Beam prediction for high-mobility vehicles.
• Tracking of pedestrians and cyclists.

ISAC does not replace all vehicle sensors, but it can add a network-level sensing layer.

References for this section3

• F. Liu et al., "Integrated Sensing and Communications", IEEE JSAC, 2022.
• J. A. Zhang et al., "An Overview of Signal Processing Techniques for Joint Communication and Radar Sensing", IEEE JSTSP, 2021.
• Z. Yang et al., "RIS-Enabled ISAC: A Sensing-Assisted Communication Framework", Frontiers in Communications and Networks, 2023.

2. Smart Factories

Factories need low-latency communication and safety awareness. ISAC can provide control links for robots while sensing human workers, moving machines, and blocked paths.

Use cases:

• Robot-zone safety.
• Asset tracking.
• Human presence detection.
• Predictive beam management in metallic environments.

References for this section3

• F. Liu et al., "Integrated Sensing and Communications", IEEE JSAC, 2022.
• J. A. Zhang et al., "An Overview of Signal Processing Techniques for Joint Communication and Radar Sensing", IEEE JSTSP, 2021.
• Z. Yang et al., "RIS-Enabled ISAC: A Sensing-Assisted Communication Framework", Frontiers in Communications and Networks, 2023.

3. Contactless Healthcare

Radio sensing can detect chest motion, breathing patterns, falls, and movement without wearable devices. ISAC could combine patient connectivity with environmental monitoring.

This must be treated carefully because healthcare sensing raises privacy, reliability, and regulatory questions.

References for this section3

• F. Liu et al., "Integrated Sensing and Communications", IEEE JSAC, 2022.
• J. A. Zhang et al., "An Overview of Signal Processing Techniques for Joint Communication and Radar Sensing", IEEE JSTSP, 2021.
• Z. Yang et al., "RIS-Enabled ISAC: A Sensing-Assisted Communication Framework", Frontiers in Communications and Networks, 2023.

4. Drone and UAV Tracking

Cellular ISAC can detect, track, and communicate with UAVs. This is useful for:

• Delivery-drone corridors.
• Unauthorized drone detection.
• Airspace monitoring.
• Beam alignment for aerial users.

References for this section3

• F. Liu et al., "Integrated Sensing and Communications", IEEE JSAC, 2022.
• J. A. Zhang et al., "An Overview of Signal Processing Techniques for Joint Communication and Radar Sensing", IEEE JSTSP, 2021.
• Z. Yang et al., "RIS-Enabled ISAC: A Sensing-Assisted Communication Framework", Frontiers in Communications and Networks, 2023.

5. Gesture and Human Activity Recognition

High-frequency radio echoes can capture motion signatures. ISAC can support gesture control, occupancy detection, and activity recognition in smart homes or industrial spaces.

References for this section3

• F. Liu et al., "Integrated Sensing and Communications", IEEE JSAC, 2022.
• J. A. Zhang et al., "An Overview of Signal Processing Techniques for Joint Communication and Radar Sensing", IEEE JSTSP, 2021.
• Z. Yang et al., "RIS-Enabled ISAC: A Sensing-Assisted Communication Framework", Frontiers in Communications and Networks, 2023.

6. Sensing-Assisted Communication

This is one of the most practical early ISAC benefits. Sensing can estimate user position, velocity, and blockage. The network can use that information to:

• Predict beams.
• Reduce beam-training overhead.
• Avoid blocked links.
• Schedule users more intelligently.

References for this section3

• F. Liu et al., "Integrated Sensing and Communications", IEEE JSAC, 2022.
• J. A. Zhang et al., "An Overview of Signal Processing Techniques for Joint Communication and Radar Sensing", IEEE JSTSP, 2021.
• Z. Yang et al., "RIS-Enabled ISAC: A Sensing-Assisted Communication Framework", Frontiers in Communications and Networks, 2023.

Takeaway

ISAC use cases are strongest when communication decisions benefit from knowing the physical state of the environment. The most credible early applications are beam management, localization, tracking, industrial sensing, and V2X support.

References for this section3

• F. Liu et al., "Integrated Sensing and Communications", IEEE JSAC, 2022.
• J. A. Zhang et al., "An Overview of Signal Processing Techniques for Joint Communication and Radar Sensing", IEEE JSTSP, 2021.
• Z. Yang et al., "RIS-Enabled ISAC: A Sensing-Assisted Communication Framework", Frontiers in Communications and Networks, 2023.