Merge commit 'v2.6.39' into 20110526
[linux-2.6.git] / Documentation / DocBook / dvb / dvbproperty.xml
1 <section id="FE_GET_PROPERTY">
2 <title>FE_GET_PROPERTY/FE_SET_PROPERTY</title>
3
4 <section id="isdbt">
5         <title>ISDB-T frontend</title>
6         <para>This section describes shortly what are the possible parameters in the Linux
7                 DVB-API called "S2API" and now DVB API 5 in order to tune an ISDB-T/ISDB-Tsb
8                 demodulator:</para>
9
10         <para>This ISDB-T/ISDB-Tsb API extension should reflect all information
11                 needed to tune any ISDB-T/ISDB-Tsb hardware. Of course it is possible
12                 that some very sophisticated devices won't need certain parameters to
13                 tune.</para>
14
15         <para>The information given here should help application writers to know how
16                 to handle ISDB-T and ISDB-Tsb hardware using the Linux DVB-API.</para>
17
18         <para>The details given here about ISDB-T and ISDB-Tsb are just enough to
19                 basically show the dependencies between the needed parameter values,
20                 but surely some information is left out. For more detailed information
21                 see the following documents:</para>
22
23         <para>ARIB STD-B31 - "Transmission System for Digital Terrestrial
24                 Television Broadcasting" and</para>
25         <para>ARIB TR-B14 - "Operational Guidelines for Digital Terrestrial
26                 Television Broadcasting".</para>
27
28         <para>In order to read this document one has to have some knowledge the
29                 channel structure in ISDB-T and ISDB-Tsb. I.e. it has to be known to
30                 the reader that an ISDB-T channel consists of 13 segments, that it can
31                 have up to 3 layer sharing those segments, and things like that.</para>
32
33         <para>Parameters used by ISDB-T and ISDB-Tsb.</para>
34
35         <section id="isdbt-parms">
36                 <title>Parameters that are common with DVB-T and ATSC</title>
37
38                 <section id="isdbt-freq">
39                         <title><constant>DTV_FREQUENCY</constant></title>
40
41                         <para>Central frequency of the channel.</para>
42
43                         <para>For ISDB-T the channels are usually transmitted with an offset of 143kHz. E.g. a
44                                 valid frequncy could be 474143 kHz. The stepping is bound to the bandwidth of
45                                 the channel which is 6MHz.</para>
46
47                         <para>As in ISDB-Tsb the channel consists of only one or three segments the
48                                 frequency step is 429kHz, 3*429 respectively. As for ISDB-T the
49                                 central frequency of the channel is expected.</para>
50                 </section>
51
52                 <section id="isdbt-bw">
53                         <title><constant>DTV_BANDWIDTH_HZ</constant> (optional)</title>
54
55                         <para>Possible values:</para>
56
57                         <para>For ISDB-T it should be always 6000000Hz (6MHz)</para>
58                         <para>For ISDB-Tsb it can vary depending on the number of connected segments</para>
59
60                         <para>Note: Hardware specific values might be given here, but standard
61                                 applications should not bother to set a value to this field as
62                                 standard demods are ignoring it anyway.</para>
63
64                         <para>Bandwidth in ISDB-T is fixed (6MHz) or can be easily derived from
65                                 other parameters (DTV_ISDBT_SB_SEGMENT_IDX,
66                                 DTV_ISDBT_SB_SEGMENT_COUNT).</para>
67                 </section>
68
69                 <section id="isdbt-delivery-sys">
70                         <title><constant>DTV_DELIVERY_SYSTEM</constant></title>
71
72                         <para>Possible values: <constant>SYS_ISDBT</constant></para>
73                 </section>
74
75                 <section id="isdbt-tx-mode">
76                         <title><constant>DTV_TRANSMISSION_MODE</constant></title>
77
78                         <para>ISDB-T supports three carrier/symbol-size: 8K, 4K, 2K. It is called
79                                 'mode' in the standard: Mode 1 is 2K, mode 2 is 4K, mode 3 is 8K</para>
80
81                         <para>Possible values: <constant>TRANSMISSION_MODE_2K</constant>, <constant>TRANSMISSION_MODE_8K</constant>,
82                                 <constant>TRANSMISSION_MODE_AUTO</constant>, <constant>TRANSMISSION_MODE_4K</constant></para>
83
84                         <para>If <constant>DTV_TRANSMISSION_MODE</constant> is set the <constant>TRANSMISSION_MODE_AUTO</constant> the
85                                 hardware will try to find the correct FFT-size (if capable) and will
86                                 use TMCC to fill in the missing parameters.</para>
87
88                         <para><constant>TRANSMISSION_MODE_4K</constant> is added at the same time as the other new parameters.</para>
89                 </section>
90
91                 <section id="isdbt-guard-interval">
92                         <title><constant>DTV_GUARD_INTERVAL</constant></title>
93
94                         <para>Possible values: <constant>GUARD_INTERVAL_1_32</constant>, <constant>GUARD_INTERVAL_1_16</constant>, <constant>GUARD_INTERVAL_1_8</constant>,
95                                 <constant>GUARD_INTERVAL_1_4</constant>, <constant>GUARD_INTERVAL_AUTO</constant></para>
96
97                         <para>If <constant>DTV_GUARD_INTERVAL</constant> is set the <constant>GUARD_INTERVAL_AUTO</constant> the hardware will
98                                 try to find the correct guard interval (if capable) and will use TMCC to fill
99                                 in the missing parameters.</para>
100                 </section>
101         </section>
102         <section id="isdbt-new-parms">
103                 <title>ISDB-T only parameters</title>
104
105                 <section id="isdbt-part-rec">
106                         <title><constant>DTV_ISDBT_PARTIAL_RECEPTION</constant></title>
107
108                         <para><constant>If DTV_ISDBT_SOUND_BROADCASTING</constant> is '0' this bit-field represents whether
109                                 the channel is in partial reception mode or not.</para>
110
111                         <para>If '1' <constant>DTV_ISDBT_LAYERA_*</constant> values are assigned to the center segment and
112                                 <constant>DTV_ISDBT_LAYERA_SEGMENT_COUNT</constant> has to be '1'.</para>
113
114                         <para>If in addition <constant>DTV_ISDBT_SOUND_BROADCASTING</constant> is '1'
115                                 <constant>DTV_ISDBT_PARTIAL_RECEPTION</constant> represents whether this ISDB-Tsb channel
116                                 is consisting of one segment and layer or three segments and two layers.</para>
117
118                         <para>Possible values: 0, 1, -1 (AUTO)</para>
119                 </section>
120
121                 <section id="isdbt-sound-bcast">
122                         <title><constant>DTV_ISDBT_SOUND_BROADCASTING</constant></title>
123
124                         <para>This field represents whether the other DTV_ISDBT_*-parameters are
125                                 referring to an ISDB-T and an ISDB-Tsb channel. (See also
126                                 <constant>DTV_ISDBT_PARTIAL_RECEPTION</constant>).</para>
127
128                         <para>Possible values: 0, 1, -1 (AUTO)</para>
129                 </section>
130
131                 <section id="isdbt-sb-ch-id">
132                         <title><constant>DTV_ISDBT_SB_SUBCHANNEL_ID</constant></title>
133
134                         <para>This field only applies if <constant>DTV_ISDBT_SOUND_BROADCASTING</constant> is '1'.</para>
135
136                         <para>(Note of the author: This might not be the correct description of the
137                                 <constant>SUBCHANNEL-ID</constant> in all details, but it is my understanding of the technical
138                                 background needed to program a device)</para>
139
140                         <para>An ISDB-Tsb channel (1 or 3 segments) can be broadcasted alone or in a
141                                 set of connected ISDB-Tsb channels. In this set of channels every
142                                 channel can be received independently. The number of connected
143                                 ISDB-Tsb segment can vary, e.g. depending on the frequency spectrum
144                                 bandwidth available.</para>
145
146                         <para>Example: Assume 8 ISDB-Tsb connected segments are broadcasted. The
147                                 broadcaster has several possibilities to put those channels in the
148                                 air: Assuming a normal 13-segment ISDB-T spectrum he can align the 8
149                                 segments from position 1-8 to 5-13 or anything in between.</para>
150
151                         <para>The underlying layer of segments are subchannels: each segment is
152                                 consisting of several subchannels with a predefined IDs. A sub-channel
153                                 is used to help the demodulator to synchronize on the channel.</para>
154
155                         <para>An ISDB-T channel is always centered over all sub-channels. As for
156                                 the example above, in ISDB-Tsb it is no longer as simple as that.</para>
157
158                         <para><constant>The DTV_ISDBT_SB_SUBCHANNEL_ID</constant> parameter is used to give the
159                                 sub-channel ID of the segment to be demodulated.</para>
160
161                         <para>Possible values: 0 .. 41, -1 (AUTO)</para>
162                 </section>
163
164                 <section id="isdbt-sb-seg-idx">
165
166                         <title><constant>DTV_ISDBT_SB_SEGMENT_IDX</constant></title>
167
168                         <para>This field only applies if <constant>DTV_ISDBT_SOUND_BROADCASTING</constant> is '1'.</para>
169
170                         <para><constant>DTV_ISDBT_SB_SEGMENT_IDX</constant> gives the index of the segment to be
171                                 demodulated for an ISDB-Tsb channel where several of them are
172                                 transmitted in the connected manner.</para>
173
174                         <para>Possible values: 0 .. <constant>DTV_ISDBT_SB_SEGMENT_COUNT</constant> - 1</para>
175
176                         <para>Note: This value cannot be determined by an automatic channel search.</para>
177                 </section>
178
179                 <section id="isdbt-sb-seg-cnt">
180                         <title><constant>DTV_ISDBT_SB_SEGMENT_COUNT</constant></title>
181
182                         <para>This field only applies if <constant>DTV_ISDBT_SOUND_BROADCASTING</constant> is '1'.</para>
183
184                         <para><constant>DTV_ISDBT_SB_SEGMENT_COUNT</constant> gives the total count of connected ISDB-Tsb
185                                 channels.</para>
186
187                         <para>Possible values: 1 .. 13</para>
188
189                         <para>Note: This value cannot be determined by an automatic channel search.</para>
190                 </section>
191
192                 <section id="isdb-hierq-layers">
193                         <title>Hierarchical layers</title>
194
195                         <para>ISDB-T channels can be coded hierarchically. As opposed to DVB-T in
196                                 ISDB-T hierarchical layers can be decoded simultaneously. For that
197                                 reason a ISDB-T demodulator has 3 viterbi and 3 reed-solomon-decoders.</para>
198
199                         <para>ISDB-T has 3 hierarchical layers which each can use a part of the
200                                 available segments. The total number of segments over all layers has
201                                 to 13 in ISDB-T.</para>
202
203                         <section id="isdbt-layer-ena">
204                                 <title><constant>DTV_ISDBT_LAYER_ENABLED</constant></title>
205
206                                 <para>Hierarchical reception in ISDB-T is achieved by enabling or disabling
207                                         layers in the decoding process. Setting all bits of
208                                         <constant>DTV_ISDBT_LAYER_ENABLED</constant> to '1' forces all layers (if applicable) to be
209                                         demodulated. This is the default.</para>
210
211                                 <para>If the channel is in the partial reception mode
212                                         (<constant>DTV_ISDBT_PARTIAL_RECEPTION</constant> = 1) the central segment can be decoded
213                                         independently of the other 12 segments. In that mode layer A has to
214                                         have a <constant>SEGMENT_COUNT</constant> of 1.</para>
215
216                                 <para>In ISDB-Tsb only layer A is used, it can be 1 or 3 in ISDB-Tsb
217                                         according to <constant>DTV_ISDBT_PARTIAL_RECEPTION</constant>. <constant>SEGMENT_COUNT</constant> must be filled
218                                         accordingly.</para>
219
220                                 <para>Possible values: 0x1, 0x2, 0x4 (|-able)</para>
221
222                                 <para><constant>DTV_ISDBT_LAYER_ENABLED[0:0]</constant> - layer A</para>
223                                 <para><constant>DTV_ISDBT_LAYER_ENABLED[1:1]</constant> - layer B</para>
224                                 <para><constant>DTV_ISDBT_LAYER_ENABLED[2:2]</constant> - layer C</para>
225                                 <para><constant>DTV_ISDBT_LAYER_ENABLED[31:3]</constant> unused</para>
226                         </section>
227
228                         <section id="isdbt-layer-fec">
229                                 <title><constant>DTV_ISDBT_LAYER*_FEC</constant></title>
230
231                                 <para>Possible values: <constant>FEC_AUTO</constant>, <constant>FEC_1_2</constant>, <constant>FEC_2_3</constant>, <constant>FEC_3_4</constant>, <constant>FEC_5_6</constant>, <constant>FEC_7_8</constant></para>
232                         </section>
233
234                         <section id="isdbt-layer-mod">
235                                 <title><constant>DTV_ISDBT_LAYER*_MODULATION</constant></title>
236
237                                 <para>Possible values: <constant>QAM_AUTO</constant>, QP<constant>SK, QAM_16</constant>, <constant>QAM_64</constant>, <constant>DQPSK</constant></para>
238
239                                 <para>Note: If layer C is <constant>DQPSK</constant> layer B has to be <constant>DQPSK</constant>. If layer B is <constant>DQPSK</constant>
240                                         and <constant>DTV_ISDBT_PARTIAL_RECEPTION</constant>=0 layer has to be <constant>DQPSK</constant>.</para>
241                         </section>
242
243                         <section id="isdbt-layer-seg-cnt">
244                                 <title><constant>DTV_ISDBT_LAYER*_SEGMENT_COUNT</constant></title>
245
246                                 <para>Possible values: 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, -1 (AUTO)</para>
247
248                                 <para>Note: Truth table for <constant>DTV_ISDBT_SOUND_BROADCASTING</constant> and
249                                         <constant>DTV_ISDBT_PARTIAL_RECEPTION</constant> and <constant>LAYER</constant>*_SEGMENT_COUNT</para>
250
251                                 <informaltable id="isdbt-layer_seg-cnt-table">
252                                         <tgroup cols="6">
253
254                                                 <tbody>
255                                                         <row>
256                                                                 <entry>PR</entry>
257                                                                 <entry>SB</entry>
258                                                                 <entry>Layer A width</entry>
259                                                                 <entry>Layer B width</entry>
260                                                                 <entry>Layer C width</entry>
261                                                                 <entry>total width</entry>
262                                                         </row>
263
264                                                         <row>
265                                                                 <entry>0</entry>
266                                                                 <entry>0</entry>
267                                                                 <entry>1 .. 13</entry>
268                                                                 <entry>1 .. 13</entry>
269                                                                 <entry>1 .. 13</entry>
270                                                                 <entry>13</entry>
271                                                         </row>
272
273                                                         <row>
274                                                                 <entry>1</entry>
275                                                                 <entry>0</entry>
276                                                                 <entry>1</entry>
277                                                                 <entry>1 .. 13</entry>
278                                                                 <entry>1 .. 13</entry>
279                                                                 <entry>13</entry>
280                                                         </row>
281
282                                                         <row>
283                                                                 <entry>0</entry>
284                                                                 <entry>1</entry>
285                                                                 <entry>1</entry>
286                                                                 <entry>0</entry>
287                                                                 <entry>0</entry>
288                                                                 <entry>1</entry>
289                                                         </row>
290
291                                                         <row>
292                                                                 <entry>1</entry>
293                                                                 <entry>1</entry>
294                                                                 <entry>1</entry>
295                                                                 <entry>2</entry>
296                                                                 <entry>0</entry>
297                                                                 <entry>13</entry>
298                                                         </row>
299                                                 </tbody>
300
301                                         </tgroup>
302                                 </informaltable>
303
304                         </section>
305
306                         <section id="isdbt_layer_t_interl">
307                                 <title><constant>DTV_ISDBT_LAYER*_TIME_INTERLEAVING</constant></title>
308
309                                 <para>Possible values: 0, 1, 2, 3, -1 (AUTO)</para>
310
311                                 <para>Note: The real inter-leaver depth-names depend on the mode (fft-size); the values
312                                         here are referring to what can be found in the TMCC-structure -
313                                         independent of the mode.</para>
314                         </section>
315                 </section>
316         </section>
317 </section>
318 </section>