100 km One-Point to Multi-Point Simultaneous Laser Communication Based on 8×8 Matrix Vector Optical Phased Array

Laser communication has become the trend of future low earth orbit (LEO) satellite interconnection, and one-point to multi-point communication plays an important role in satellite laser communication network. At present, the main method is that one satellite carries multiple traditional laser communication terminals, which may be costly and weighted. In view of the above contradiction, an 8×8 matrix vector optical phased array (VOPA) laser communication terminal prototype was investigated. The 8×8 matrix can realize arbitrary array element beam combination, and 4 beams are taken as an example to verify the multi-point communication. Using the phase error separation and decoupling technology, the beam combining efficiency of each subarray was greater than 70%, and an optical antenna with an equivalent aperture of 38.08 mm was obtained and beam steering range of 50°×43°can be achieved in the proposed VOPA. The communication distance of the 4 beams was 100 km and the maximum communication capacity was 40 Gbps with the modulation format of on-off keying (OOK), and the bit error rate (BER) was less than 10E-9 without forward error correction (FEC). By adding the control of tip/tilt dimension, the VOPA can solve the problem that the traditional OPA needs a large number of elements. This work fully verifies the feasibility and superiority of the VOPA, which will become an essential component of the satellite optical communication system, and gives the one-point to multi-point simultaneous laser communication method based on the VOPA.