We require the delivery of two optical terminals to DSTG Edinburgh by the end of Q4 2025 that can establish a point-to-point optical link. These terminals will have the following nominal specifications:

• Performance:
• Carry optical timing signals at 1550 nm at eye-safe power levels (Class 1 or 1M) as per the AS/NZS IEC 60825.12:2023 standard (required)
• Carry optical timing signals at 810 nm at the single-photon-level (desired)
• Average optical link loss of less than 30 dB across a 1.5 km link, including coupling out of, and in to, single-mode fibre (SMF) for monostatic operation, or into SMF or multi-mode fibre (MMF) for bi-static operation
• Have sufficient pointing bandwidth to track angle-of-arrival fluctuations in high turbulence environments (Cn2 > 10-14 m-2/3), including SMF coupling
• Size <50 L per terminal, not including the mount
• Weight <30 kg per terminal, not including the mount
• Acquisition and tracking:
• The terminals should be able to acquire and stabilise a stationary optical point-to-point link between themselves autonomously, and maintain the link for significant periods of time (hours to days) without physical intervention from an operator (required)
• The terminals should be able to track each other if one is moving relative to the other (desired)
• Inputs/outputs:
• 1550 nm SMF fibre in/out in either monostatic (SMF fibre) or bi-static (SMF Tx, SMF or MMF Rx) arrangement. Connector type (i.e., FC/APC, FC/PC) and arrangement (i.e., one fibre for Tx and Rx, or separate Tx and Rx fibres) to be agreed upon
• If applicable, 810 nm fibre in/out in either monostatic (SMF fibre) or bi-static (SMF Tx, SMF or MMF Rx) arrangement. Connector type (i.e., FC/APC, FC/PC) and arrangement to be agreed upon.
• SMF in/out. Connector type (i.e., FC/APC, FC/PC) and arrangement (i.e., one fibre for Tx and Rx, or separate Tx and Rx fibres) to be agreed upon
• Technical Readiness Level (TRL): 5 or above