From e7f6f6e6217e4c26d1dba2acc2c9cacbeb1f62a2 Mon Sep 17 00:00:00 2001 From: Patrick Boettcher Date: Tue, 4 Aug 2009 14:15:17 +0200 Subject: ISDB-T: Added note about DTV_FREQUENCY for From: Patrick Boettcher Added information about DTV_FREQUENCY in the document. Priority: normal Signed-off-by: Patrick Boettcher --- dvb-spec/ISDB-T_and_ISDB-Tsb_with_S2API | 28 ++++++++++++++++++++-------- 1 file changed, 20 insertions(+), 8 deletions(-) (limited to 'dvb-spec') diff --git a/dvb-spec/ISDB-T_and_ISDB-Tsb_with_S2API b/dvb-spec/ISDB-T_and_ISDB-Tsb_with_S2API index ef1a05973..e2df2b4d9 100644 --- a/dvb-spec/ISDB-T_and_ISDB-Tsb_with_S2API +++ b/dvb-spec/ISDB-T_and_ISDB-Tsb_with_S2API @@ -26,20 +26,32 @@ Parameters used by ISDB-T and ISDB-Tsb. Existing parameters =================== -a) DTV_BANDCOUNT_HZ +a) DTV_FREQUENCY -Help the front-end, for example, to set up base-band-filters. +Central frequency of the channel. + +For ISDB-T the channels are usally transmitted with an offset of 143kHz. E.g. a +valid frequncy could be 474143 kHz. The stepping is bound to the bandwidth of +the channel which is 6MHz. + +As in ISDB-Tsb the channel consists of only one or three segments the +frequency step is 428kHz, 3*428 respectively. As for ISDB-T the +central frequency of the channel is expected. + +b) DTV_BANDWIDTH_HZ + +Help the front-end, for example, to set up base-band-filters correctly. Possible values: For ISDB-T it should be always 6000000Hz (6MHz) For ISDB-Tsb it can vary depending on the number of connected segments -b) DTV_DELIVERY_SYSTEM +c) DTV_DELIVERY_SYSTEM Possible values: SYS_ISDBT -c) DTV_TRANSMISSION_MODE +d) DTV_TRANSMISSION_MODE ISDB-T supports three carrier/symbol-size: 8K, 4K, 2K. It is called 'mode' in the standard: Mode 1 is 2K, mode 2 is 4K, mode 3 is 8K @@ -48,18 +60,18 @@ Possible values: TRANSMISSION_MODE_2K, TRANSMISSION_MODE_8K, TRANSMISSION_MODE_AUTO, TRANSMISSION_MODE_4K If DTV_TRANSMISSION_MODE is set the TRANSMISSION_MODE_AUTO the -hardware will try to find the correct FFT-size (if capable) and use -the TMCC to fill in the missing parameters. +hardware will try to find the correct FFT-size (if capable) and will +use TMCC to fill in the missing parameters. TRANSMISSION_MODE_4K is added at the same time as the other new parameters. -d) DTV_GUARD_INTERVAL +e) DTV_GUARD_INTERVAL Possible values: GUARD_INTERVAL_1_32, GUARD_INTERVAL_1_16, GUARD_INTERVAL_1_8, GUARD_INTERVAL_1_4, GUARD_INTERVAL_AUTO If DTV_GUARD_INTERVAL is set the GUARD_INTERVAL_AUTO the hardware will -try to find the correct guard interval (if capable) and use the TMCC to fill +try to find the correct guard interval (if capable) and will use TMCC to fill in the missing parameters. New parameters -- cgit v1.2.3