IP-recovery in the DVB-H Link layer for TV on mobile
Recently, DVB-H Internet Protocol based TV on Mobile devices made its entrance in the mobile arena. Due to transmission over an error-prone channel, IP datagrams (packet at network layer) may be corrupted. To improve reception robustness, the DVB-H link layer is equipped with Forward Error Correction (FEC), allowing correction of erroneous IP datagrams, using two-bit signaling information. During reception, locator information is derived prior to FEC, indicating the storage position of correctly received IP datagrams. This is essential due to the variable-length sizes of the IP-based data. For the situation that FEC fails to correct all erroneously received data, the locator information enables retrieval of all correctly received IP datagrams and indicates the location of potentially corrected IP datagrams. Using the derived locator information, experimental research has shown that after FEC, a considerable number of correct IP datagrams can still be recovered from an incorrect MPE-FEC frame. This results in up to 50% data recovery for medium-sized datagrams. This successful recovery depends on the received IP datagram length and the transmission error probability and results in an improved audiovisual decoding quality.