ISAC-Aware MAC Scheduling — Telecom Resource

MAC Overview Scheduling Beamforming OFDM Power Control Sidelink AI Scheduling NTN MAC Energy-Saving MAC IAB MAC Cell-Free MAC

1. Resource Split — Comm vs Sensing

ISAC splits time-frequency resources between communication and sensing. Three strategies: time-division, frequency-division, or joint optimization (same PRBs for both).

Resource Grid — Comm PRBs vs Sensing PRBs

Adjust the ratio between communication and sensing resources. See the impact on throughput and sensing accuracy.

Sensing ratio: 30% Strategy:

Frequency Division

Split PRBs: some for comm, some for sensing. Simultaneous operation. Sensing resolution limited by allocated BW.

Time Division

Alternate comm and sensing slots. No cross-interference. Each function gets only 50% of time.

Joint Optimization

Same PRBs serve both. OFDM waveform carries data AND forms sensing signal. Maximum efficiency.

2. Dual-Objective Scheduler

The ISAC scheduler optimizes alpha x Throughput + beta x Sensing Accuracy. Adjusting the weights shifts the operating point along the Pareto frontier.

Pareto Frontier — Throughput vs Sensing Accuracy

Drag the slider to move along the trade-off curve. No single point maximizes both objectives.

Comm priority (alpha): 0.60

Pareto-optimal: Moving along the frontier, increasing one objective requires decreasing the other. The scheduler selects the point based on current scenario (V2X emergency = sensing-priority, normal traffic = comm-priority).

3. Waveform Parameter Trade-offs

OFDM parameters affect both comm and sensing differently. Wider bandwidth improves data rate AND range resolution. Higher SCS reduces latency but may limit velocity resolution.

Waveform Trade-offs — SCS, Bandwidth, CP

Adjust parameters and see the impact on communication rate vs sensing resolution.

Bandwidth (MHz): 100 SCS (kHz):

Parameter	Communication	Sensing
Wider BW	Higher data rate	Finer range resolution
Higher SCS	Lower latency	Wider unambiguous velocity
Longer CP	More robust	Longer max range
More symbols	More capacity	Finer velocity resolution

4. Practical Field Considerations

Use Case	Sensing Function	MAC Config
V2X (Vehicle)	Obstacle/pedestrian detection	Sensing priority, real-time
Indoor (Smart Home)	Gesture/presence	Low-power, periodic
Drone Detection	Airspace monitoring	Wide BW, high priority
Health (Wearable)	Heart rate, breathing	Ultra-low power, short-range

Self-interference challenge: Monostatic ISAC (gNB TX+RX) needs 120+ dB dynamic range for self-interference cancellation. Bistatic (separate TX/RX) avoids this but requires coordination.

5. 6G Evolution — Sensing-First Networks

Full ISAC Integration

Every transmission senses. No separate mode. MAC treats sensing as equal to communication.

THz Sensing

100-300 GHz: sub-mm resolution. Molecular spectroscopy. Imaging through walls.

Sensing-as-a-Service

Network sells sensing data. Traffic monitoring, environmental, security. MAC schedules sensing bearers.

ISAC Evolution — Comm-Only to Sensing-First

Compare ISAC capabilities across generations.

Generation:

Dimension	5G (Current)	5G-Advanced	6G (Target)
ISAC mode	Separate systems	Overlay (some PRBs)	Joint waveform
Resolution	N/A	~1m (100 MHz)	Sub-mm (THz)
Scheduling	Comm-only	Dual-objective	Sensing-first
Cooperation	None	Bistatic	Multi-static mesh