Question: How is the energy detection threshold (`θ`) determined for an eNB/gNB accessing a shared spectrum channel when the absence of other technologies sharing the channel cannot be guaranteed on a long-term basis?
Option 1: θ = Maximum energy detection threshold defined by regulatory requirements in dBm, if available, otherwise a fixed value of -125 dBm.
Option 2: θ = Minimum (`P_max_eNB/gNB` - 5dB), where `P_max_eNB/gNB` is the maximum eNB/gNB output power in dBm for the channel.
Option 3: θ = Minimum (`P_max_eNB/gNB` - `M`) - 5dB, where `P_max_eNB/gNB` is the maximum eNB/gNB output power in dBm, and `M` depends on the transmission type (e.g., 0dB for most transmissions, with exceptions).
Option 4: θ = Maximum energy detection threshold set to a fixed value of -120 dBm for all regulatory regions and bands.
Explanation: When the absence of other technologies cannot be guaranteed, the energy detection threshold (`θ`) is determined more dynamically, considering the maximum transmission power of the eNB/gNB (`P_max_eNB/gNB`), a margin (`M`) that can vary based on the type of transmission (e.g., presence of discovery bursts), and an additional fixed reduction of 5dB. This approach ensures sensitivity to detect other potential transmissions while avoiding false positives, reflecting the nuanced adaptation required in shared spectrum environments.