6.1.1.1. Frontend type

For historical reasons, frontend types are named by the type of modulation used in transmission. The fontend types are given by fe_type_t type, defined as:

fe_type

Frontend types

fe_type	Description	DTV_DELIVERY_SYSTEM equivalent type
FE_QPSK	For DVB-S standard	SYS_DVBS
FE_QAM	For DVB-C annex A standard	SYS_DVBC_ANNEX_A
FE_OFDM	For DVB-T standard	SYS_DVBT
FE_ATSC	For ATSC standard (terrestrial) or for DVB-C Annex B (cable) used in US.	SYS_ATSC (terrestrial) or SYS_DVBC_ANNEX_B (cable)

Newer formats like DVB-S2, ISDB-T, ISDB-S and DVB-T2 are not described at the above, as they're supported via the new FE_GET_PROPERTY/FE_GET_SET_PROPERTY ioctl's, using the DTV_DELIVERY_SYSTEM parameter.

In the old days, struct dvb_frontend_info used to contain fe_type_t field to indicate the delivery systems, filled with either FE_QPSK, FE_QAM, FE_OFDM or FE_ATSC. While this is still filled to keep backward compatibility, the usage of this field is deprecated, as it can report just one delivery system, but some devices support multiple delivery systems. Please use DTV_ENUM_DELSYS instead.

On devices that support multiple delivery systems, struct dvb_frontend_info::fe_type_t is filled with the currently standard, as selected by the last call to FE_SET_PROPERTY using the DTV_DELIVERY_SYSTEM property.