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Digital Video

Carrier

Carrier Actions

AddCarrier

Adds a new carrier to the last position in the carrier list.

CopyCarrier

Copies the settings of the currently selected carrier and adds a new carrier with these settings.

DeleteCarrier

Deletes the selected carrier from the list.

CarrierCount

Query only

Displays the total number of carriers defined in the list.

Basic

State

Turns the operating state of the carrier to on or off.

Format

The format of the carrier. Currently, only the DVB-S2/S2X format is supported.

Frequency Offset

Sets the frequency offset for the carrier relative to the signal generator’s frequency setting. The valid range will be different for each format due to the different oversampling ratios.

For example, for 2 carriers configuration, set the center frequency of signal generator to 1 GHz, and make the two carriers distributed on both sides of the center frequency with 5 MHz offset each. The actual frequency of each carrier would then be 1 GHz + 5 MHz and 1 GHz - 5 MHz respectively.

Initial Phase

Sets the initial phase of the carrier.

Power

Sets the carrier’s power relative to the signal generator’s amplitude setting.

DVB-S2/S2X Settings

Filter Type

Selects the filter type for the carrier.

• Nyquist : Conventionally, a data transmission system employs a Nyquist filter whose reply for an impulse is zero (0) for every interval T just before and after a peak (T: data transmission interval). As replies of adjacent data are zero on a sample point of other sampled data, interference between codes can be prevented.
  To function as above, a Nyquist filter whose amplitude becomes half at the point where Nyquist frequency fN (=1/2T) is used, and it is odd-symmetrically rolled off with a squared cosine around the half amplitude point in the cutoff area. In this case the phase characteristics is not considered, or is designed to have linear phase characteristics usually.
  

• Root Nyquist: Instead of a simple Nyquist filter, low-pass filters (root Nyquist filters) having equal amplitude are set for transmission and reception and their characteristics are made the same as that of the Nyquist filter above. In this case, the root Nyquist filter must have cosine characteristics that can be made the squared cosine characteristics above.

Roll-off Factor

Selects the roll-off factor for DVB-S2/S2X transmission according to ETSI EN 302 307-2 Section 5.1.6.

Standard Encoding (ETSI EN 302 307-2 Section 5.1.6):

• 00: 0.35 (DVB-S2)

• 01: 0.25 (DVB-S2)

• 10: 0.20 (DVB-S2)

• 11,00,11,00...: 0.15 (DVB-S2X alternating pattern)

• 11,01,11,01...: 0.10 (DVB-S2X alternating pattern)

• 11,10,11,10...: 0.05 (DVB-S2X alternating pattern)

DVB-S2/S2X have taken into consideration of various requirements of multiple service. For one thing, it supports a wide range of code rates (from 1/4 up to 9/10); for another, roll-off factor can be selected among 0.35, 0.25, 0.2, instead of the fixed 0.35 in DVB-S.

Symbol Rate

Sets the symbol rate of DVB-S2/S2X.

The symbol rate is matched to given transponder characteristics, since DVB-S.2 is suitable for use on different satellite transponder bandwidths and frequency bands, and in the case of multiple carriers per transponder (FDM), to the frequency plan adopted.

Dummy Frame

Turns the generation of dummy frames on or off.

When enabled, the carrier generates dummy PL Frames.

Support DVB-S2X

Enables or disables the support for DVB-S2X.

VL-SNR Header

Enables or disables the insertion of VL-SNR Header in PLFRAME in DVB-S2X.

BB Header

Enables or disables the transmition of BBHEADER in BBFRAME.

CCM/ACM

Selects the coding mode:

• CCM (Constant Coding and Modulation): Uses fixed modulation and code rate for all transmission.

• ACM (Adaptive Coding and Modulation): Dynamically adjusts modulation and code rate based on channel conditions.

This setting determines the value for the corresponding data field in MATYPE-1 in BB Header.

FEC Frame

Selects whether to use normal, medium or short LDPC block size in DVB-S2/S2X.

FEC encoding performs outer coding (BCH), Inner Coding (LDPC), and Bit interleaving. The input stream is composed of BBFRAMEs and the output stream of FECFRAMEs. Each BBFRAME (Kbch bits) shall be processed by the FEC coding subsystem, to generate a FECFRAME (nldpc bits). The parity check bits (BCHFEC) of the systematic BCH outer code shall be appended after the BBFRAME, and the parity check bits (LDPCFEC) of the inner LDPC encoder shall be appended after the BCHFEC field, as shown below.

FEC Encoding Data Structure

LDPC encoding provides two kinds of frame length, one is normal frame with length 64800 bit; the other is short frame with length 16200 bit (1/4 of normal frame), shown in the following figure.

Table 1 FECFRAME (normal and short) configurations and application areas

Modulation Type

Selects the modulation type.

Code Rate

Selects the LDPC code rate of DVB-S2/S2X.

Insert Pilot

Selects whether to insert pilot at the physical layer in DVB-S2/S2X. For the VL-SNR Header, Insert Pilot is always ON.

When Insert Pilot is set to ON, a PILOT BLOCK composed of P = 36 pilot symbols is inserted. Each pilot is an un-modulated symbol, identified by I = (1/√2), Q = (1/√2). The first PILOT BLOCK shall be inserted 16 SLOTs after the PLHEADER, the second after 32 SLOTs and so on. If the PILOT BLOCK position coincides with the beginning of the next SOF, then the PILOT BLOCK is not transmitted. Besides, the pilot presence/absence in VCM (Variable Coding and Modulation) and ACM (Adaptive Coding and Modulation) can be changed on a frame-by-frame basis.

CRC-8 Encoder for User Packet

Selects whether to use CRC-8 before channel coding in DVB-S2/S2X.

Number of PL Frames

Total Length of BB Frames (bits)

Gold Sequence Index

Sets the Gold Sequence Index for PL Scrambling.

Multi-Path Channel

Click the > button displayed on the right side of the Multi-Path Channel setting to open the Multi-path Channel configuration window.

A multi-path channel which contains up to 20 paths can be set according to your test requirements.

State

Turns the multi-path channel on or off.

Attenuation in dB

Delay (us)

Attenuation

Phase (rad)

Time Slicing Settings

Time Slicing Structure

Selects whether to use time slicing structure defined in Annex M in ETSI EN 302 307-1.

For more information, see Time Slicing Structure in Tutorials.

See also, DVB-S2/S2X Time Slicing (TSL) Settings configuration.

TSN Enabled

Selects whether to use the 180 symbols PL Header with TSN in DVB-S2X Time Slicing.

TSL Sequence

Sets the time slicing pattern to configure the permutation of TSLs. When number of TSLs is more than one, this can be an array. The array is surrounded by "[" and "]", and the elements are separated by ",". The Number of PL Frames can be calculated by the size of "Time Slicing Pattern" array.

TSN (Hex) Sequence

Query only

Gets the TSN Sequence pattern for each TSLs.

MODCOD Sequence

Query only

Gets the MODCOD Sequence pattern for each TSLs.

PLFRAME Length Sequence

Query only

Gets the PLFRAME Length Sequence pattern for each TSLs.

Time Slicing (TSL) Settings

AddTsl

RemoveTsl

CopyTsl

TslCount

TSL

Query only

Displays the time slice number.

TSN (Hex)

Sets the 8-bit sized time slice number (TSN) in hex for the respective time slice.

Dummy Frame

Enables or disables Dummy Frame.

When enabled, the carrier generates dummy PL Frames.

VL-SNR Header

Selects whether to insert VL-SNR Header in PLFRAME in DVB-S2X.

FEC Frame

Selects whether to use normal, medium, or short LDPC block size in DVB-S2/S2X.

FEC encoding performs outer coding (BCH), Inner Coding (LDPC) and Bit interleaving. The input stream is composed of BBFRAMEs and the output stream of FECFRAMEs. Each BBFRAME (Kbch bits) shall be processed by the FEC coding subsystem, to generate a FECFRAME (nldpc bits). The parity check bits (BCHFEC) of the systematic BCH outer code shall be appended after the BBFRAME, and the parity check bits (LDPCFEC) of the inner LDPC encoder shall be appended after the BCHFEC field, as shown below.

FEC Encoding Data Structure

LDPC encoding provides two kinds of frame length, one is normal frame with length 64800 bit; the other is short frame with length 16200 bit (1/4 of normal frame), shown in the following figure.

Table 2 FECFRAME (normal and short) configurations and application areas

Code Rate

Sets the LDPC code rate for each physical frame.

Modulation Type

Selects the modulation type.

Insert Pilot

Selects whether to insert pilot at the physical layer in DVB-S2/S2X.

For the VL-SNR mode, Insert Pilot is always On.

When Insert Pilot is enabled, a PILOT BLOCK composed of P = 36 pilot symbols is inserted. Each pilot is an un-modulated symbol, identified by I = (1/√2), Q = (1/√2). The first PILOT BLOCK shall be inserted 16 SLOTs after the PLHEADER, the second after 32 SLOTs and so on. If the PILOT BLOCK position coincides with the beginning of the next SOF, then the PILOT BLOCK is not transmitted. Besides, the pilot presence/absence in VCM (Variable Coding and Modulation) and ACM (Adaptive Coding and Modulation) can be changed on a frame-by-frame basis.

PLFRAME Length

Query only

Gets the length for each physical layer frame in TSL. This is read-only and calculated by PLS.

Data Source Type

Selects which type to be used as the data source.

• When the payload is selected as "Test Pattern", the test signal is a stream of pure PRBS without any TS framing structure. PRBS, all ones or all zeros, could be used as the basic serial BER stream.

• When the payload is selected as "Binary Pattern File", you can browse and select a Binary Pattern file as the data source.   

Pattern Bits

Sets the data bits to be used as test pattern.

Click the > button displayed on the right side of the Pattern Bits setting to open the Pattern Bits dialog and select a test pattern to use.

Binary Pattern File

Sets the Binary Patten File to be used as the data source when the payload is selected as "Binary Pattern File",

SYNC Insertion

Determine whether a SYNC byte (0x47) should be inserted into the test pattern.

Super Frame Settings

Super Frame Structure

Selects whether to use super frame structure defined in Annex E in ETSI EN 302 307-2.

For more information, see Super Frame Structure.

Super Frame Format

Selects the format of super frame structure. Only Format 5 and Format 6 are currently supported.

Number of Super Frames

Sets the number of super frames blocks to be generated.

Pilot

Sets whether to add SF-pilot.

When number of super frames is more than one, this can be an array. The array is surrounded by “[“ and “]”, and the elements are separated by “,”.

Postamble Sequence Length (L)

Query only

Gets tThe length of postamble sequence. This is the "L" value defined in E3.7.8. This is read-only and defined by the highest protection level in the dwell.

Postamble Switching Length

Sets the length of postamble filled by (1+1j)/sqrt(2).

When number of super frames is more than one, this can be an array. The array is surrounded by "[" and "]", and the elements are separated by ",". 0 means this super frame is not the last frame in the dwell and there is no postamble in this super frame.

Number of CU in Super Frame

Sets the number of capacity unit (CU) in each super frame.

When number of super frames is more than one, this can be an array. The array is surrounded by "[" and "]", and the elements are separated by ",".

Number of Symbols in Super Frame (SFL)

Query only

Gets the number of symbols in each super frame. This is SFL in Annex E. This is read-only and calculated by Number of CU in Super Frame, Pilot, Postamble Sequence Length, and Postamble Switching Length.

Super Frame Length (us)

Query only

Gets the Super Frame duration, in microseconds (us). This read-only value is automatically calculated as :

(Number of Symbols in Super Frame) / (Symbol Rate) × 1,000,000

When multiple Super Frames are configured, values are displayed as an array.

Number of PL Frames in Each Super Frame

Sets the number of physical layer frames in each super frame. When number of super frames is more than one, this can be an array. The array is surrounded by "[" and "]", and the elements are separated by ",".

Fragmentation

Sets the fragmentation in the first super frame. The unit is CU.

Reset Data Input for Different Super Frame

Sets whether to reset data input for different cells for multi-cell cases.

• When set to off, the input bit stream is continuous from cell to cell.

• When set to on, the input stream is reset from cell to cell.

Cell Destination

Sets the cell destination in each super frame.

When number of super frames is more than one, this can be an array. The array is surrounded by "[" and "]", and the elements are separated by ",".

When the super frame doesn’t have enough symbols for physical layer data, the remining physical data will be transmitted in the following super frame with the same cell destination as fragmentation.

SFH Pointer

Query only

Gets the pointer to the first complete PLH (counting in CU). This is read-only and defined by fragmentation and other super frame / physical frame settings.

When number of super frames is more than one, this will be an array.

Overflow Length

Query only

Gets the overflow length for each superframe.

The Overflow of the last superframe of the Cell is discarded.

BB Scrambling

Sets whether the baseband scrambling will be used before FEC.

The BB scrambling is defined in 5.2.2 in ETSI EN 302 307-1.

PLH Protection Level

Sets the PLH protect level.

When number of super frames is more than one, this can be an array. The array is surrounded by "[" and "]", and the elements are separated by ",".

Two-way Scrambling

Sets whether the two-way scrambling will be used.

Two-way scrambling is defined in defined in E2.4.

Reference Data Scrambler Index (nRef)

Payload Data Scrambler Index (nPay)

SOSF Sequence Index

Sets the row index for Start of Super-Frame (SOSF) field. When the number of super frames is more than one, this can be an array. The array is surrounded by "[" and "]", and the elements are separated by ",".

Pilot Sequence Index

Sets the row index for SF-Pilot field. When the number of super frames is more than one, this can be an array. The array is surrounded by "[" and "]", and the elements are separated by ",".

TSN List

Sets the TSN value for each physical frame.

When the number of physical frames is more than one, this can be an array. The array is surrounded by "[" and "]", and the elements are separated by ",".

The number of physical layer frames can be calculated by summing up the values in Number of PL Frames in Each Super Frame array.

PLFRAME Length (Symbols)

Query only

Gets the length for each physical layer frame in TSL. This is read-only and calculated by PLS.

System Level Signalling in SFH (2 bits)

Sets the last two bits in PLH.

When the number of super frames is more than one, this can be an array. The array is surrounded by "[" and "]", and the elements are separated by ",".

PLS List

Sets the PLS value for each physical frame. When the number of physical frames is more than one, this can be an array. The array is surrounded by "[" and "]", and the elements are separated by ",". The number of physical layer frames can be calculated by summing up the values in Number of PL Frames in Each Super Frame array.

Modulation Type List

Query only

Gets the modulation type for each physical frame.

Code Rate List

Query only

Gets the LDPC code rate for each physical frame.

FEC Frame List

Query only

Gets the FEC frame type for each physical frame.

Spreading List

Query only

Gets the spreading value for each physical frame.

BBFRAME Length (kbch) List (bits)

Query only

Displays the BBFRAME (Baseband Frame) length, in bits for each physical frame. This is a read-only field and automatically calculated from the PLS List.

The BBFRAME length represents Kbch (the number of information bits in the baseband frame before LDPC encoding). This is calculated based on:

• FEC frame size (Normal/Medium/Short)

• Code rate

• Modulation type

The BBFRAME length determines:

• How much user data can be carried in each frame

• The efficiency of the transmission

• Buffer sizes required for processing

Values are specified in ETSI EN 302 307-1 Table 6a (Normal/Short frames) and ETSI EN 302 307-2 Table 5-2 (Medium frames and DVB-S2X code rates).

GSE Settings

GSE

Enables or disables Generic Stream Encapsulation (GSE) according to ETSI TS 102 771.

When GSE is enabled, the CRC-8 Encoder is automatically disabled. GSE provides its own error detection through CRC-32 checksums on fragmented packets.

PDU Length (bytes)

Sets the Protocol Data Unit (PDU) length, in bytes. The PDU is the unit of data that will be encapsulated into GSE packets.

This value must be at least 15 bytes. It affects how many GSE packets will be generated for the data stream.

Number of PDUs

Query only

Displays the total number of Protocol Data Units (PDUs) that will be generated. This is a read-only auto calculated value based on the data source configuration and PDU length.

Each PDU represents one complete data unit that will be encapsulated into one or more GSE packets according to ETSI TS 102 771.

Number of GSE Packets

Query only

Displays the total number of GSE packets that will be generated. This is a read-only auto calculated value.

The number of GSE packets depends on the relationship between PDU Length and GSE Length:

• If PDU fits completely: 1 GSE packet per PDU

• If fragmentation is needed: Multiple packets per PDU (START + INTERMEDIATE + END fragments)

Label Type

Selects the label type for GSE encapsulation:

• Type 0: 6-byte label (48-bit MAC address)

• Type 1: 3-byte label (24-bit address)

• Type 2: No label

The label identifies the destination or stream for the encapsulated data according to ETSI TS 102 771 Section 4.2.

Changing the Label Type will automatically adjust the maximum allowed Label value.

Label (Hex)

Sets the label value, in hexadecimal format. The label is used to identify the destination address or stream for the GSE packets.

• For Label Type 0, enter a 12-digit hex value representing a 48-bit MAC-48 address.

• For Label Type 1, enter a 6-digit hex value representing a 24-bit address.

The label is included in the GSE header for START fragments and complete packets according to ETSI TS 102 771.

Fragment ID (Hex)

Sets the initial Fragment ID, in hexadecimal format (2 hex digits). The Fragment ID is a 8-bit value (0-255) used to identify fragments belonging to the same PDU.

When a PDU is fragmented into multiple GSE packets (START, INTERMEDIATE, END), all fragments of the same PDU share the same Fragment ID. The Fragment ID is automatically incremented for each new PDU according to the formula:

nextFragID := (fragID + 1) mod 256

The Fragment ID appears in the GSE header for START, INTERMEDIATE, and END fragments as specified in ETSI TS 102 771 Section 4.2.

Protocol Type (Hex)

Sets the Protocol Type field, in hexadecimal format. This 16-bit field identifies the type of payload carried in the GSE packet.

Common values:

• 0x0800: IPv4

• 0x86DD: IPv6

• 0x0000: Custom or unspecified

The Protocol Type is included in the GSE header for complete packets and START fragments according to ETSI TS 102 771 Section 4.2.2. It follows the EtherType numbering scheme from IEEE 802.

Data Source Settings

Supported File Size

Query only

Gets the supported file size for current settings.

Useful Bit Rate

Query only

Displays the useful bit rate. The bit rate is determined by the current bandwidth, encoding, modulation, and framing configurations.

Data Source Type

Selects which type to be used as the data source.

• Test Pattern: When the payload is selected as Test Pattern, the test signal is a stream of pure PRBS without any TS framing structure. PRBS, all ones or all zeros, could be used as the basic serial BER stream.

• Binary Pattern File: When the payload is selected as Binary Pattern File, you need to specify the file name.

Pattern Bits

Sets the data bits to be used as test pattern.

Click the > button displayed on the right side of the Pattern Bits setting to open the Pattern Bits dialog and select a test pattern to use.

Binary Pattern File

Sets the Binary Patten File to be used as the data source when the payload is selected as "Binary Pattern File",

SYNC Insertion

Determines whether a SYNC byte (0x47) should be inserted into the test pattern.