The utility model relates to a high-definition asymmetric transmission system comprising a mainboard which is arranged in a shell of a field portable application terminal. A programmable base-band manager, an MPU-end processor, a programmable brightness filtering controller, a programmable aberration filtering controller and a burst inhibition and compression processor are integrated on the mainboard and electrically connected. The programmable brightness filtering controller is connected with a first 16-path filter via a signal converter. The programmable aberration filtering controller is connected with a second 16-path filter via a digital harmonic synthesizer. The burst inhibition and compression processor is connected with a 4-path filter via an HD signal converter. The first 16-path filter, the second 16-path filter and the 4-path filter are connected with the programmable base-band manager and three 11-bit digital-to-analog converters via multipath modulators. Space bandwidth can all be distributed to one segment of transmission so that non-equilibrium directional cross work can be realized. Besides, the high-definition asymmetric transmission system is small in volume and light in weight so that the portable application requirement is met.