Johannes Stezenbach wrote:
On Fri, May 26, 2006, Manu Abraham wrote:
Johannes Stezenbach wrote:
It really a bummer that EN 300 468 uses the term
"normative broadcast mode" without defining it,
It indeed says, in the very first line.
Normative Broadcast Mode (NBC-BS) [This is (Non Backwards Compatible -
Broadcast Service) ]
Page 12 (Abbreviations) EN 300 468
NBC-BS Non Backwards Compatible Broadcast Services (DVB-S2)
And it refers the same to EN 302 307, what it is in S2 satellite
delivery system descriptor
So what is the confusion ?
Good question, however I think you are the one who
is confused, not me ;-/
Ok, Let me try to understand, where i am wrong.
"Normative Broadcast Mode (NBC-BS)" IS NOT A DEFINITION
OF THE TERM "Normative Broadcast Mode".
The DEFINITION is missing, so we have to guess. And yeah,
I initially guessed wrong and did understand it differently,
but now I think I have figured it out.
You mean you found this somewhere ? Or do you mean Normative as found in
NOTE 3: in table 1 ?
but I am now convinced that "normative broadcast mode (NBC-BS)"
means "those parts of NBC-BS which are mandatory",
i.e. "normative broadcast mode" means a subset of NBC-BS.
I thought NBC-BS = Non Backward Compatible - Broadcast Service
Look at EN 302 307 table 1.
*Looking at 302 307 Table 1*
They just mean it is Optional, that means those parameters can be there
or not, that is what i understand from the table. It is *not* a must
that, VCM since marked as "O" is Normative Broadcast Mode or Backward
Compatible
To clarify my understanding of table 1:
It says what NBC-BS is, and it says what the normative (i.e. mandatory)
and optional parts of NBC-BS are.
(Note: "normative" is the exact wording used in table 1)
1. table 1 is about NBC only (i.e. DVB-S2 only, not receivable
by DVB-S receivers
That is 100% sure, no doubt about it.
2. ...since BC is defined in annex F, i.e. is not part of table 1
That also i agree ..
3. table 1 defines Broadcast, Interactive, DSNG and
Professional services
Right
-> all normative and optional featues in the BS column are
what comprises "NBC-BS".
MIS is an optional part of NBC-BS. So when EN 300 468 says
"Normative Broadcast Mode (NBC-BS)" it means:
no MIS, no VCM, less moduleaton types and fec modes
This is consistent with "In normative broadcast
mode the satellite_delivery_system_descriptor is sufficient",
since the noramtive parts of NBC-BS don't need the
input_stream_identifier etc.
Agreed. NBC-BS does not need ISI
This also means that the S2 description is not only used
for BC modes, but also for NBC modes which use MIS
(which are optional, but exist according ot table 1).
Two cases, in case (1) S2 satellite delivery system descriptor _is_ present.
in case (2) S2 satellite delivery system descriptor is _not_ present.
(1)
Transport_stream_loop_length: 698 (0x02ba)
Transport_stream_ID: 6 (0x0006)
Original_network_ID: 133 (0x0085) [= BetaTechnik | BetaTechnik]
reserved_1: 15 (0x0f)
Transport_descriptor_length: 27 (0x001b)
DVB-DescriptorTag: 65 (0x41) [= service_list_descriptor]
descriptor_length: 9 (0x09)
service_ID: 129 (0x0081)[ --> refers to PMT program_number]
service_type: 25 (0x19) [= advanced codec HD digital
television service]
service_ID: 130 (0x0082)[ --> refers to PMT program_number]
service_type: 25 (0x19) [= advanced codec HD digital
television service]
service_ID: 131 (0x0083)[ --> refers to PMT program_number]
service_type: 25 (0x19) [= advanced codec HD digital
television service]
DVB-DescriptorTag: 67 (0x43) [=
satellite_delivery_system_descriptor]
descriptor_length: 11 (0x0b)
Frequency: 18420816 (= 11.91450 GHz)
Orbital_position: 402 (= 19.2)
West_East_flag: 1 (0x01) [= EAST]
Polarisation: 0 (0x00) [= linear - horizontal]
Kind: 1 (0x01) [= DVB-S2]
Roll Off Faktor: 0 (0x00) [= Alpha 0.35]
Modulation_type: 1 (0x01) [= QPSK]
Symbol_rate: 2576384 (= 27.5000)
FEC_inner: 9 (0x09) [= 9/10 conv. code rate]
DVB-DescriptorTag: 121 (0x79) [=
S2_satellite_delivery_system_descriptor]
descriptor_length: 1 (0x01)
scrambling_sequence_selector: 0 (0x00)
multiple_input_stream_flag: 0 (0x00)
backwards_compatibility_indicator: 0 (0x00)
reserved_future_use: 0 (0x00)
(2)
Transport_stream_ID: 6 (0x0006)
Original_network_ID: 133 (0x0085) [= BetaTechnik | BetaTechnik]
reserved_1: 15 (0x0f)
Transport_descriptor_length: 13 (0x000d)
DVB-DescriptorTag: 67 (0x43) [=
satellite_delivery_system_descriptor]
descriptor_length: 11 (0x0b)
Frequency: 18420816 (= 11.91450 GHz)
Orbital_position: 402 (= 19.2)
West_East_flag: 1 (0x01) [= EAST]
Polarisation: 0 (0x00) [= linear - horizontal]
Kind: 1 (0x01) [= DVB-S2]
Roll Off Faktor: 0 (0x00) [= Alpha 0.35]
Modulation_type: 1 (0x01) [= QPSK]
Symbol_rate: 2576384 (= 27.5000)
FEC_inner: 9 (0x09) [= 9/10 conv. code rate]
Manu
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