你可以看看TBS6981,它是一款双输入频头的卫星接收卡，并且支持双调制，你可以看看它的官方网站描述：
supports dual DVB-S2 TV channels receiving synchronously, which enables you to watch channel from one transporder/satellite while recording another channel from another transporder/satellite. Or you can use one channel for data download while watching TV in another channel in the same time.
TBS6981 is ideal for building HTPC under Linux MythTV, VDR, XBMC and Windows 7 Media Center.
希望对你能有所帮助：
http://www.buydvb.net/tbs6981-pcie-dvbs2-dual-tuner-tv-card_p11.html