(dvb-t) Transmodulator Ttx311

Transcript

9. Technical specifications RF output parameters Modulation Bandwidth Guard interval Code rate transparent Mode multiplexed RF output frequency RF offset (7 MHz) RF offset (8 MHz) Attenuation Nominal output level Carrier stability MER Output impedance RF input parameters Modulation Input frequency Input level Input impedance Loop through gain Signal/Noise Mini modular headend MMH3000 DVB-T QPSK, QAM16, QAM64 7 MHz, 8 MHz 1/4, 1/8, 1/16, 1/32 1/2, 2/3, 3/4, 5/6, 7/8 2k, 8k 2k 110...860 MHz by 0.5 MHz step -125 kHz, 0, +125 kHz -166 kHz, 0, +166 kHz 0...15.5 dB by 0.5 dB step 90 dBμV ±1.5 dB ± 500 Hz ≥ 35.0 dB 75 Ω DVB-T QPSK, QAM16, QAM64 104 ... 862 MHz 40 ... 100 dBμV 75 Ω 0 ... +3.5 dB ≥ 23 dB COFDM to COFDM (DVB-T) transmodulator ttx311 1. Product description The ttx311 is DVB-T receiver with DVB-T modulator and transport stream remultiplexer with transparent modulator option. It is intended to receive DVB-T signal, restore lost data (if still technically possible) and modulate the signal again into DVB-T RF channel. It can also be used in multiplexed mode (filter services or modify parameters of transport stream). Transmodulator is intended to use in the MMH3000 headend. ttx311 is designed in accordance with standard EN50083-5 class 2. The unit is intended for indoor usage only. RoHS compliant. 2. Safety instructions Any repairs must be performed by a qualified personnel. Module shall not be exposed to dripping or splashing water and no objects filled with liquids, such as vases, shall be placed on it. Avoid placing module next to central heating components and in areas of high humidity. No naked flame sources, such as lighted candles, should be placed on module. If the module has been kept in cold conditions for a long time, keep it in a warm room no less than 2 hours before plugging into the mains. The ventilation should not be impeded by covering with items, such as newspapers, table-cloths, curtains. This product complies with the relevant clauses of the European Directive 2002/96/EC. The unit must be recycled or discarded according to applicable local and national regulations. 3. Electrostatic discharge caution Caution: The module contain electrostatic sensitive components. To minimize electrostatic discharge, observe the following precautions: - Do not remove module from their antistatic plastic bag until you are ready to install it into the basic unit. - Hold the module only by the front panel of module. - Do not place the module on an unprotected surface. Immediately after you remove a module from the basic unit, you must insert it into its antistatic plastic bag. - When the module is not in use, keep it in their antistatic plastic bag. - Do not ship or store module near strong electrostatic, electromagnetic or radioactive fields. Multiplexing parameters (multiplexed mode only) Input bit rate Output bit rate Input services PID filter Version monitoring PMT PAT SDT PCR restamping EPG (EIT) multiplexing Other parameters Supply voltage Current consumption Output for ext. preamplifier Operating temperature range Dimensions /Weight ≤ 31.5 MBit/s ≤ 31.5 MBit/s (modulator bandwidth limited) ≤ 256 ≤ 256 Yes No No Yes Yes 5.5 ± 0.1 V 1.4 A 12 V 0.1 A, max. see UC360, UC380 manuals technical characteristics 47.5 x 117 x 220.5 mm / 0.7 kg 4. External view and operating control [1] - indicator of addressing [2] - indicator of module's status [3] - MPEG2 TS output connector [4] - RF input of DVB-T signal, preamplifier powering [5] - RF loop through output [6] - fixing screws 5. Installation instructions Draugystes str. 22, LT-51256 Kaunas, Lithuania, tel.: +370 37 - 31 34 44, fax: +370 37 - 31 35 55 E-mail: [email protected], http://www.terraelectronics.com Figure 1. External view of module Read the instruction first. Disconnect base unit from the mains before insertion/changing the module. Before pushing the module into the direction of bus bar, carefully put the edges of module PCB into grooved guides, stamped in the base unit. Fasten the module by supplied fixing screws. Place serrated lock washer with external teeth on module and nut on adapters as described in the user manuals of base units UC360, UC380. After 7-10 seconds of powering the module will run in normal operation mode. RF input signal can be connected directly to [4] connector, or via loop through outputs of other modules. Any other module's DVB-T RF input (or analog TV RF input) can be connected to ttx311 loop through output [5]. Comments of the front panel indicators: [ 1 ] - Address indicator. It lights on green when the module is addressed on Terra Bus bus. Blinking indicator indicates addressing error. [ 2 ] - Status indicator. It lights on red when any error occurs. It will start blinking at power on to indicate a starting up status. 6. Default settings DVB-T receiver parameters: - Input Frequency, kHz: 474000 - Bandwidth, MHz 8 DVB-T modulator parameters: - Modulation QAM64 - Bandwidth: 8 MHz - Guard interval: 1/32 - Code rate: 7/8 - Cell ID: 0 - RF: Off - Saw filter: Off - RF Frequency: 474 MHz - RF Offset: 0 kHz - Attenuator: 0.0 dB OFDM Output stream parameters (in multiplexed mode only): - Transport Stream ID: 1 - Network ID: 1 - Network Name: none - Date/Time source: DVB-T Input - Timing zone: 0 GMT - NIT: Disabled - EPG Multiplexing: Enabled 7. Operating Device receives DVB-T signal and outputs transport stream to connector [3] transparently (without any modification). This signal can be connected to other devices of MMH headend, which accepts TS. In case of multiplexed mode, system processes incoming transport stream (measures bitrate, generates PSI, filters services, restamples PCR, multiplexes EPG) and passes to modulator. System monitors PMT tables (up to 32) and updates the output of multiplexer if any changes detected (for example: new stream detected, new descriptors added or removed). In case of transparent mode, incomming transport stream passes directly to modulator without any modification of transport stream. Only PCR restamping is turned on in this mode. All parameters can be setup via user friendly graphic interface, which supports Terra Link, CMH Master software, PCS200 server. "Home" tab of ttx311's control panel will appear when device was selected (see corresponding software user manual). See Figure 2. Figure 2. Home tab of ttx311 control panel Three sections exist on this page. "Input channel" table shows parameters of incoming transport stream (DVB-T demodulator). "Signal status" shows transport stream detection status. "Bit Rate" shows bit rate of incoming transport stream. "Output channel" table shows parameters of outgoing transport stream. "Max. Bitrate" - this is the maximum available output bit rate according to OFDM modulation parameters (code rate, guard interval, etc). "Current Bitrate" shows bitrate of outgoing transport stream. "Used bandwidth" value is calculated from previous two values, and indicates the percentage of used bandwidth. NOTE: Ensure that used bandwidth would not exceed 95%. Otherwise bit rate overflow would occurs. In case of bitrate overflow error, indicated bitrate values will be inaccurate because a device can not measure bitrate in such error condition. "System status" table indicates main information about the device (device name, serial number, software and hardware version, internal temperature, system time). This table also will show all errors of device operation. Device has internal clock, and a value 1970.01.01 00:00:00 will be assigned after system startup. The clock will be updated automatically from transport stream TDT table. Information on this page is updated automatically in real time. 2 Input stream => Rescan Command will erase previous list of services, and rescan new list. After scanning, all services are disabled. Each service must be enabled individually. Input stream => "Enter" key will toggle selection of the service. If the second character has "^" sign, it means that the service is selected. Otherwise it is disabled. Input stream => Save & Run Will save all information, generate all SI tables and run with new settings. Input Params => Input Freq. DVB-T input frequency, kHz. Input Params => Input Bandw. DVB-T input channel bandwidth (7 or 8 MHz). Input Params => Preamp. Power DVB-T input antenna powering On/Off. OFDM Params => Modulation Allows to select the modulation (constellation) between QPSK, QAM16 and QAM64. OFDM Params => Bandwidth Allows to select the bandwidth of the RF output between 7 and 8 MHz. OFDM Params => Guard Interval Allows to select guard interval between 1/4, 1/8, 1/16 and 1/32. OFDM Params => Code Rate Allows to select code rate between 1/2, 2/3, 3/4, 5/6 and 7/8. OFDM Params => Cell ID Allows to enter Cell ID value 0..65535. OFDM Params => RF Allows to turn On / Off RF of modulator. OFDM Params => Saw filter Allows to turn On / Off saw filter of intermedium frequency. Parameter can be actual if analog TV channel is adjacent to OFDM channel. OFDM Params => Out. Frequency Allows to setup output frequency of modulator. OFDM Params => RF Offset Allows to setup RF offset of modulator. ±166 kHz for 8 MHz bandwidth, and ±125 kHz for 7 MHz channel. OFDM Params => Attenuator Allows to setup RF attenuation in a range of 0..15.5 dB. Network Params => Stream ID Stream ID value. Requires to execute "Save & Run" command from "Input Stream" menu. Network Params => Network ID Network ID value. Requires to execute "Save & Run" command from "Input Stream" menu. System Status => List of Errors Shows all errors of the systems. Use "Up" and "Down" buttons to review all of them. System status => Input status Shows input bitrate and C/N. It also shows RF level if tuner is unlocked. System status => Output status Shows output bitrate and the usage of available bandwidth System Info => Product Shows the name of the device. System Info => Serial Number Shows serial number of the device. System Info => Soft. Version Shows software version of the device. System Info => System time Shows system time of the device. NOTE: timing zone and date/time source must be setup correctly. These settings available only with PC control software. System Info => Temperature Shows internal temperature °C of the device. 7 Exact broadcasting parameters must be written for selected stream. All streams (modulators) must be described here and all other modulators must have the same description table. NOTE: Only terrestrial descriptor has user-friendly editor. All the reset descriptors can be added in hex format only. Values must be added according to EN 300 468 standard, starting after descriptor_length field. descriptor_tag and descriptor_length will be added/calculated automatically. NOTE: This descriptor for current modulator (current transport stream) is generated automatically according to modulation parameters. User must take care only about the rest transport stream descriptions. Spaces between hex values can be added, but it is not necessary. Press "Save and RUN" when all NIT modifications are done. Logical Channel Descriptors can be added into the 1st section of NIT, which represents services of current stream only. "Selected channels" table has a list of all currently enabled services. If "Log. channel" field is other than zero, a LCD (Logical Channel Descriptor) will be added for that channel. LOGs section Figure 3. "DVB-T Input" section of ttx311 control panel Figure 9. LOGs section of ttx311 All errors or most important events will be logged in this section. "Erase log" button allows to clear all logs. 20 records per page can be displayed. Page selector will appear on the screen if more than 20 records are in the system. This page will be refreshed automatically when a new event occurs in the system. "Download log" link allows to download all log records from the system as a text file. NOTE: This feature works with Terra Link starting from 1.6.0 version or CMH Master starting from 1.0.3.0. 8. Handheld control unit Handheld unit allows to control the most important parameters of the device. Select the ttx311 device (see user manual of handheld unit). "Control" menu item will appear. Menu tree will appear on the screen. The first character ">" marks currently selected menu item. Some menu items has "^" character in the second position of the line. It means that current menu item is checked. Use "Up" and "Down" buttons to surf through the menu. Use "Enter" key to enter into deeper submenu or execute the command associated with it. "Esc" key will exit to upper menu or cancel the execution of a command. ttx311 has the following menu tree: Input streams DVB-T Input section (see figure 3) allows to setup RF reception parameters, displays status of demodulator. "Input Frequency" - The frequency of RF input signal. Dimmension - kHz. "Bandwidth" - The bandwidth of DVB-T input channels. Possible values: 7 MHz, 8 MHz "Preamplifier Powering" - +12 V Preamplifier Powering On/Off "DVB-T receiver status" shows the status of demodulator. Device measures signal level, signal/noise ratio and shows other information of transponder (modulation, guard interval, code rate, mode). Parameters of demodulator in this page are updated in real time. Transparent mode can monitor DVB-T input channel parameters and update the output modulation parameters accordingly. Select "Update automatically on any change" option to synchronize modulation parameters automatically. DVB-T Input / Stream section (Multiplexed operating mode only) Rescan... List of services SAVE & RUN Input params Input freq. Figure 4. "DVB-T Input / Stream" section of ttx311 control panel Input bandw. This is a transport stream multiplexer section of device, which is available in "multiplexed" mode only (see "DVB-T Output" description). Valid transport stream must exists (DVB-T demodulator must be locked) to start working with this section. "Load streams" button will load information of the stream. All found services will be listed below the button. Lock symbol at the beginning of service name indicates that a service is scrambled. Next icon represents the type of service. Following icons are possible: Preamp.power OFDM params Network params Modulation Bandwidth Cell ID Out.frequency Guard interval RF RF offset Code rate Saw filter Attenuator Stream ID Network ID System status List of errors Input status - High definition television - Standard definition television - Radio Unidentified service types will not have any icon. NOTE: Lock sign only identifies a flag of SDT table, and does not check the content itself. Check "Enable" checkbox and press "Enable services" to pass that service to modulator. After few seconds a service will be activated and passed to modulator. NOTE: Press "Home" tab to see used bandwidth of selected services. Ensure that it takes not more than 90-95% of available bandwidth, and no any bitrate overflow errors are there. Press sign if you want to see or change more details about the service. New area with information about the service will be expanded. See Figure 5. Output status System info 6 Product Serial number System time Soft. version Temperature 3 In case of transparent mode original NIT (if any) will be passed to the output. Other parameters: Operating mode - this parameter switches device between two operating modes - transparent or multiplexed mode. In case of transparent mode, original transport stream passes to modulator without any modifycations. Transparent operation mode supports 2k and 8k modulation modes. In case of multiplexed mode all multiplexing features are enabled (NIT generation, service filtering). Modulator can work in 2k modulation mode only in multiplexed case. A device will be restarted after switching this parameter, and will start operating after 10 seconds. "Timing zone" selection used for system clock only, and it does not affect the output stream. This parameter exists in both operating modes, but in case of multiplexed mode, the parameter is moved to "DVB-T Output/Stream" control panel. DVB-T Output / Stream section (Multiplexed mode only) Figure 5. Service details List of all streams and other parameters will appear. Some streams will have icons, which indicates the type of the stream. Following icons are possible: - Sound stream - DVB Subtitles - Teletext - Video Language code will be visible in round brackets if presented in the stream. Lock sign identifiers conditional access streams, which affects a stream or a whole service (like in example above). Most of the streams of the service can be disabled (filtered) by unchecking "Enabled" check box. A service name and service provider name can be changed here. "Monitoring" check box turns on monitoring of PMT version changes. If it is checked, new PMT table will be reloaded if the version of the table is changed. New appeared streams will be added to the service automatically. Disappeared streams will be removed from the service as well. The device does not take into account possible bit rate overflow of new multiplex. User must take care about it. Use this feature only in case if it is necessary. If unsure, leave it unchecked. "Scrambled" flag can be switched on/off. If the flag is off, SDT table will be generated without "scrambled" flag and all CA descriptors will be removed from the service. Press "Update program information" button to modify details of the service. NOTE: "Enable services" button will need to be pressed to save all the changes and for them to take effect. DVB-T Output section Figure 6. OFDM parameters of ttx311 control panel There are three tables in this section - modulator parameters, RF parameters and other parameters. Modulator parameters: Modulation - modulation type. Possible values: QPSK, QAM16, QAM64 Bandwidth - 7 or 8 MHz Guard interval - 1/4, 1/8, 1/16, 1/32 Code rate - 1/2, 2/3, 3/4, 5/6, 7/8 Cell ID: - Any value 0..65535 can be entered. Mode: - 2k/8k (2k only in case of multiplexed operating mode) RF parameters: RF On/Off - Allows to switch RF On or Off at the output Saw filter - Enable or disable 8 MHz (or 7 MHz) saw filter at intermediate (36 MHz) frequency. If the frequency offset ±166/125 kHz is used, a filter will be switched off automatically. RF Frequency - Output frequency of modulated COFDM signal. Step - 0.5 MHz. RF Offset - Output frequency offset ±166 kHz or ±125 kHz in 7 MHz bandwidth case. Attenuator - RF Output attenuation in 0.0 .. 15.5 dB range. NOTE: terrestrial_delivery_descriptor in NIT will be changed automatically after a change of any modulation parameters in multiplexed operating mode. Open "DVB-T Output/Stream" tab and press "Save & Run" to save new values of descriptor. 4 Figure 7. OFDM Output/Stream parameters of ttx311 Output stream parameters can be configured in this section. The most important parameters are Stream ID and Network ID. User must ensure that Network ID number is identical in all broadcasting equipments, and Transport stream ID must be unique for every modulator or other streaming equipment. “Private Data Specifier” field optionally can be used to identify the broadcaster or country. It should be assigned according to EN 101 162 specification. All allocated values can be find here: http://www.dvbservices.com/identifiers/private_data_spec_id Hexadecimal value should be entered here. The descriptor will be used together with LCN descriptor. If unsure - enter zero. In that case the Private_Data_Specifier will not be used at all. "Network Name" used in NIT (Network Identification Table) and it represents broadcaster. "Date/Time source" selects the source of the clock. TDT (Time and Date Table) will be passed to the output from selected source. Also a system clock will capture current time values from this source. "Timing zone" selection used for system clock only and it does not affect the output stream. TOT (Time Offset Table) is passed transparently to the output from selected source, which carry timing zone information to the end-user. "NIT Enable" parameter allows to turn On/Off NIT generation. "EPG Multiplexing" parameter allows to turn On/Off multiplexing of EPG (Electronic Program Guide). The system will multiplex EPG (EIT) if this parameter is turned on. EPG multiplexing part takes original EIT (Event Information Table), modifies StreamID, NetworkID values, and sends the stream to the output of multiplexer. EIT will be passed (multiplexed) for enabled services only. New button "Save and RUN" will appear if any value of this section was changed. Press it to save all changes and run the system with modified values. Next important part of this section is NIT configuration. Broadcaster can describe whole network there, so receivers (TV, settop-boxes) will be able to scan all channels automatically. The most important note to remember - Network ID number must be identical in all broadcasting equipments and Transport stream ID must be unique for every modulator or other streaming equipment. Enter NetworkID and StreamID values in "New Stream Description" table to start describing a stream (the output of each modulator in the system). New empty record for that stream will appear above that table. Press sign to expand a description and add all necessary descriptors for that stream. Select a descriptor (probably only "terrestrial_delivery_system_descriptor" will need) from the list and press "Create new descriptor" button. New empty descriptor will be added. Press onto again to expand stream description. New inserted descriptor will be found. Press onto to edit it's values (see Figure 8). Figure 8. Terrestrial descriptor 5