High speed real-time digital multi beam forming system mainly uses optical fiber transmission technology to transmit data, however, optical fiber may be limited by size, luminous decay, price, installation, etc. The introduction of high-definition digital video transmission technology can effectively solve this problem. This paper proposes a coaxial cable multi-beam data transmission scheme, which consists of high-speed serial transceiver, driver, equalizer, etc. Its principle is to achieve high-speed transmission of multi-beam data based on serial digital interface technology. Simulation experiments and physical tests have been carried out, and the simulation and test results show that this scheme can achieve the same performance as the optical fiber transmission scheme.