As one of the three communication experiments to be performed on the ECP payload of the LEO satellite ROCSAT-1, the direct broadcasting of digital TV signals using Ka-band experiment has been well planned and prepared. In this experiment, suitable compression and protection methods for the digitized video and audio signals in the LEO and Ka-band environments will be studied. The bitrate will be between 6.6 and 3.3 Mbps, depending on the affordable link budget. The carrier frequency of the uplink is 28.25 GHz, while that of the downlink is 18.45GHz. Because of the strong dependence of system performance on the channel characteristics, a realistic Ka-band channel model suitable for the subtropic Taiwan area will also be developed.