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media: fe_property_parameters.rst: better document bandwidth

Use a table to document the supported bandwidths. That makes it clearer to readers.

Mauro Carvalho Chehab committed 9 years ago

Commit 7d661ed1 parent 11814151 file · +23 −15Browse files

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Documentation/media/uapi/dvb/fe_property_parameters.rst+23−15
@@ -116,29 +116,37 @@ Should be set only for terrestrial delivery systems. · 115 unmodified lines
116Possible values: ``1712000``, ``5000000``, ``6000000``, ``7000000``,116Possible values: ``1712000``, ``5000000``, ``6000000``, ``7000000``,
117``8000000``, ``10000000``.117``8000000``, ``10000000``.
118 118
119.. note::119======================= =======================================================
120Terrestrial Standard Possible values for bandwidth
121======================= =======================================================
122ATSC (version 1) No need to set. It is always 6MHz.
123DMTB No need to set. It is always 8MHz.
124DVB-T 6MHz, 7MHz and 8MHz.
125DVB-T2 1.172 MHz, 5MHz, 6MHz, 7MHz, 8MHz and 10MHz
126ISDB-T 5MHz, 6MHz, 7MHz and 8MHz, although most places
127 use 6MHz.
128======================= =======================================================
120 129
121 #. DVB-T supports 6, 7 and 8MHz.
122 130
123 #. DVB-T2 supports 1.172, 5, 6, 7, 8 and 10MHz.131.. note::
124 132
125 #. ISDB-T supports 5MHz, 6MHz, 7MHz and 8MHz, although most
126 places use 6MHz.
127 133
128 #. On DVB-C and DVB-S/S2, the bandwidth depends on the symbol rate.134 #. For ISDB-Tsb, the bandwidth can vary depending on the number of
129 So, the Kernel will silently ignore setting :ref:`DTV-BANDWIDTH-HZ`.135 connected segments.
130 136
131 #. For DVB-C and DVB-S/S2, the Kernel will return an estimation of the137 It can be easily derived from other parameters
132 bandwidth, calculated from :ref:`DTV-SYMBOL-RATE` and from138 (DTV_ISDBT_SB_SEGMENT_IDX, DTV_ISDBT_SB_SEGMENT_COUNT).
133 the rolloff, with is fixed for DVB-C and DVB-S.
134 139
135 #. For DVB-S2, the bandwidth estimation will use :ref:`DTV-ROLLOFF`.140 #. On Satellite and Cable delivery systems, the bandwidth depends on
141 the symbol rate. So, the Kernel will silently ignore any setting
142 :ref:`DTV-BANDWIDTH-HZ`. I will however fill it back with a
143 bandwidth estimation.
136 144
137 #. For ISDB-Tsb, it can vary depending on the number of connected145 Such bandwidth estimation takes into account the symbol rate set with
138 segments.146 :ref:`DTV-SYMBOL-RATE`, and the rolloff factor, with is fixed for
147 DVB-C and DVB-S.
139 148
140 #. Bandwidth in ISDB-Tsb can be easily derived from other parameters149 For DVB-S2, the rolloff should also be set via :ref:`DTV-ROLLOFF`.
141 (DTV_ISDBT_SB_SEGMENT_IDX, DTV_ISDBT_SB_SEGMENT_COUNT).
142 150
143 151
144.. _DTV-INVERSION:152.. _DTV-INVERSION: