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Direct To Home (DTH) Service Provider In Europe.

DTH Service Providers in Europe
People tend to incline for entertainment doing anything they find fit for fun including fishing, traveling, reading books, web surfing, gossiping, cycling, writing, watching television and many more. And watching television is fun as well as recreational for most of the people of almost all the ages.  However, when we find ourselves in a mood to watch TV program, we also find ourselves in the need of a cable network or satellite tv service. For doing so, we can take help of direct-to-home service which is called DTH – a digital satellite television viewing services for subscribers directly through satellite transmission. That is why, we will now learn about direct-to-home service providers in entire Europe. Since above the earth, there are lot of satellites stationed at six key positions in orbit and DTH can make your day at home with variety of channels for fun and entertainment.      
In Europe, there seems to be number of DTH service providers available in the market from which you will select your preferable one which obviously meets your requirements of tv channels. We will simple begin with Canal Digital – a widely known DTH service provider for quality viewers. Established in 1997, Canal Digital goes ahead with the purpose of distributing Television programs. This remains as primary ambition for Canal Digital along with performing huge amount of activities related to broadcast and entertainment. To name few milestones of Canal Digital, it became pure subsidiary of Telenor in 2002, first Nordic Content provider to offer HDTV in 2005, Canal Digital Kabel-TV AS(Norway) becomes a part of Telenor Norway in 2010, AS is re-established fully focusing on DTH in the Nordics in 2011 and more. Canal Digital aims to reach to the customers with rich content with over 130 TV channels from where you can pick your own.  And the best thing about Canal Digital is that around 900 thousand households make their first choice to pick Canal Digital as their entertainment platform across the Nordics.

The leading DTH service provider is not only Canal Digital, the Sky is rocking high as well with endless entertainment programs and broadband. From Television to Mobile Phone, Sky is at your doorstep to entertain you with your best choice. Sky allows to explore Sky Corporate, Sky for Business, Sky Communal TV, and work for Sky. Getting bored home or anywhere in your country, just pop in Sky and enjoy the ultimate entertainment with variety of channels including Sky 1, Sky Living, Sky Atlantic, Sky Arts, Sky Cinema, Sky Sports, and Sky news as well. You will never be able to miss anything from any channel with Sky as it offers great advantage of highlighting your preferred chunks or programs or shows or sports. This is amazing for the sports lover as you can pick and choose any dedicated channels from premier league to F1 including football, cricket and golf. The opportunity of entertainment is simply enormous and quite convenient with Sky.      

Number of Choices
However, these two direct-to-home service providers are not only ruling the entire Europe, but as we will get to know about other DTH service providers and countries as well.

1. Digit-Al 

1. Sky Osterreich

1. Bulsatcom

1. Digi TV

1. Canal Digital

1. CanalSat

1. CanalDigital 

1. Sky Deutschland

1. Digi TV
2. Magyar Telekom

 1. Sky
2. Saorsat

1. Sky Italia

1. TéléSAT Luxembourg

1. CanalDigitaal
2. UPC Direct 

1. Canal Digital

1. Cyfrowy Polsat
1. ZON TV Cabo

1. Orange TV
2. RCS & RDS
3. Focus Sat

1. NTV Plus
2. Tricolor TV

1. Digi TV
2. TotalTV 

1. Digi TV

1. Movistar+

1. Canal Digital

1. Digiturk

United Kingdom
1. Sky
2. Freesat

1. Xtra TV

Overall, DTH service Providers in entire Europe are extensive with endless choices to make. Out of so many, Canal Digital and Sky can be convenient as well as full of entertainment. And the rest of the DTH service providers are best based in country and specific zones. At the end, the Tv shows, programs, sports, live channels are pretty easily accessible from every single DTH Service provider.            

How to configure encoder for satellite TV signal transmission.

Encoder Configuration

Encoding  is an essential part for satellite communication. For that reason broadcast engineers need to know how to configure the encoder properly. There are a number of encoder brand in the market. Most of them have the almost same parameter to configure. So the engineers have to put some value of the parameter to the encoder to encode signal. It depends on the demand and criteria of the TV channel owner and the signal. Some of the most important and common parameter (with dummy value) are as follows.   

1) Program name: XYZ TV
2) Service ID: 101
3) Video Format: PAL/ NTSC/ SECAM
4) Video Resulation: 720*576, 1920*1080
5) Video Bit Rate Mod: CBR/ VBR
6) Video Bit Rate (kbps): 4000
7) Audio Bit Rate (kbps): 192
8) Brightness: 50
9) Contrast: 50
10) Saturation: 50
11) Hue: 50
12) Video Encode Mode: MPEG-2
13) Audio Encode Mode: MPEG-2

That parameters define the characteristic of the up-link / transmitting signal. After encoding the signal, it goes into the modulator. Then the signal is modulated for the long distance transmission. After that, the modulated signal is amplified by SSPA or HPA to increase the amplitude of the signals. Then finally it transmitted through the web guide to the satellite.  

What is the difference between symbol rate and bit rate?

A symbol can carry multiple bits (and usually does). So BPSK/BFSK has a symbol of 2 states and the bit rate is the same as the symbol. QPSK has 4 symbol states and each symbol can carry 2 bits. 8PSK has eight symbol states and each symbol can carry 3 bits. 16QAM has 16 symbol states and each symbol can carry 4 bits. I'm sure you get the drift. 

Terminology: EIRP, G/T, Input Back-Off, Output Back-Off

EIRP: Used to indicate the power transmitted from an antenna. EIRP=Power +Antenna Gain, Both EIRP and Power is expressed in dBW and Gain in dBi.

G/T: It is the figure of merit for an earth station and is expressed as dB/K (dB per K).
G/T= Antenna Gain-10*Log (System Noise Temperature) The higher the better-G/T can be raised by using a higher gain antenna or a lower temperature LNA. The earth station G/T determines the received carrier to noise ration. Increasing station G/T will increase the C/N of the received carrier.

Input Back-Off (IPBO): The level of a signal at the input of an amplifier relative to that level at the input that would result in the maximum possible output level. For example, if an input level of -20dBm causes max output and the actual input level is -25dBm, the IPBO is 5dB. Both IPBO and OPBO are commonly used to determine the operating levels in a satellite transponder TWTA.

Output Back-Off (OPBO) The level of a signal at the output of an amplifier relative to the maximum possible output level. For example, if a maximum output level is +40dBm and the measured output level is +34dBm, the OPBO is 6dB. 

Terminology: Bandwidth, LNA Noise Temperature, Saturation Flux Density and Polarization.

Bandwidth is another fundamental antenna parameter. Bandwidth describes the range of frequencies over which the antenna can properly radiate or receive energy. Often, the desired bandwidth is one of the determining parameters used to decide upon an antenna. For instance, many antenna types have very narrow bandwidths and cannot be used for wideband operation.

Bandwidth is typically quoted in terms of VSWR (Voltage Standing Wave Ratio, and sounds very complicated. But it is simply a measure of how much power is reflected from an antenna. ) . For instance, an antenna may be described as operating at 100-400 MHz with a VSWR<1.5. This statement implies that the reflection coefficient is less than 0.2 across the quoted frequency range. Hence, of the power delivered to the antenna, only 4% of the power is reflected back to the transmitter. Alternatively, the return lossS11=20*log10(0.2)=-13.98 dB.

Note that the above does not imply that 96% of the power delivered to the antenna is transmitted in the form of EM radiation; losses must still be taken into account. 

LNA Noise Temperature: It is the measure of the amount of noise generated by the LNA. It is measured in Kelvin-the lower the better. Typical performance can be achieved for 30K to 70K. LNA noise performance is sometimes specified in terms of Noise Figure which is measured in dB.

NF=10*Log (1+T/290), NF in dB, T in Kelvins. 

Saturation Flux Density: Flux density is a measure of signal strength at a point in space and is measured in Watts/meter2 or dBW/meter2. It is usually applied to signals received at a satellite.

Polarisation: The polarisation of an RF wave in space is defined by the orientation of the electric vector (E) of the wave. The polarisation of an RF wave is used in satellite systems to separate two signals at the same frequency and allows frequency reuse in satellite systems. There are circular and linear polarizations and under each there are horizontal and vertical.

Frequency Band of Satellite communication

Due to lower frequencies, L-Band is easiest to implement for marine satellite stabilised systems. There is not much L-Band bandwidth available. The higher you go in frequency, the more bandwidth is available, but the equipment needs to be more sophisticated. 

L-Band (1-2 GHz)
Being a relatively low frequency, L-band is easier to process, requiring less sophisticated and less expensive RF equipment, and due to a wider beam width, the pointing accuracy of the antenna does not have to be as accurate as the higher bands.

L-Band is also used for low earth orbit satellites, military satellites, and terrestrial wireless connections like GSM mobile phones. It is also used as an intermediate frequency for satellite TV where the Ku or Ka band signals are down-converted to L-Band at the antenna LNB, to make it easier to transport from the antenna to the below deck, or indoor equipment. 

C-Band (4-8 GHz)
Satellite C-band usually transmits around 6 GHz and receives around 4 GHz. It uses large (2.4- 3.7 meter) antennas. These are the large white domes that you see on top of the cruise ships and commercial vessels.

C-band is typically used by large ships that traverse the oceans on a regular basis and require uninterrupted, dedicated, always on connectivity as they move from region to region.  The shipping lines usually lease segment of satellite bandwidth that is provided to the ships on a full time basis, providing connections to the Internet, the public telephone networks, and data back-hauls to their head office.

C-band is also used for terrestrial microwave links,  which can present a problem when vessels come into port and interfere with critical terrestrial links. This has resulted in serious restrictions within 300Km of the coast, requiring terminals to be turned off when coming close to land.

Ku-Band (12-18 GHz)
Ku-Band is most commonly used for satellite TV and is used for most VSAT systems on yachts and ships today. There is much more bandwidth available in Ku -Band and it is therefore less expensive that C or L-band. 

The main disadvantage of Ku-Band is rain fade. The wavelength of rain drops coincides with the wavelength of Ku-Band causing the signal to be attenuated during rain showers. This can be overcome by transmitting extra power but this of course comes with a cost as well. 

The pointing accuracy of the antennas need to be much tighter than L-Band Inmarsat terminals, due to narrower beam widths, and consequently the terminals need to be more precise and more expensive.

Ka-Band (26.5-40 GHz)
Ka-Band is an extremely high frequency requiring great pointing accuracy and sophisticated RF equipment. Like Ku-band it is susceptible to rain fade. It is commonly used for high definition satellite TV.  It is also used today for terrestrial VSAT services from companies like Hughes Networks.

Ka-Band bandwidth is plentiful and once implemented should be quite inexpensive compared to Ku-Band .  

Figure: Satellite Frequency Band of Operation 

What is Bitrate, CBR, VBR ?

What is the bitrate?
In telecommunications and computing, bit rate (sometimes written bitrate) is the number of bits that are conveyed or processed per unit of time.

Bit is the unit of information.  Remember that 1 byte consists of 8 bits. Video data rates are given in bits per second. The data rate for a video file is the bitrate. So a data rate specification for video content that runs at 1 megabyte per second would be given as a bitrate of 8 megabits per second (8 mbps). The bitrate for an HD Blu-ray video is typically in the range of 20 mbps, standard-definition DVD is usually 6 mbps, high-quality web video often runs at about 2 mbps, and video for phones is typically given in the kilobits (kbps).

Understanding bitrate in video files
It’s important to understand how the bitrate control corresponds to video quality and the file size. At the same bitrate, video in a newer codec such as H.264 will look substantially better than an older codec like H.263. Another consideration is that variable bitrate (VBR) encoding will produce better image quality than constant bitrate (CBR) in most applications.

What is Modulation ? AM, FM and PM.

In electronics and telecommunications, modulation is the process of varying one or more properties of a periodic waveform, called the carrier signal, with a modulating signal that typically contains information to be transmitted.

In telecommunications, modulation is the process of conveying a message signal, for example a digital bit stream or an analog audio signal. Modulation of a sine waveform transforms a base-band message signal into a pass-band signal.

A modulator is a device that performs modulation. A demodulator (sometimes detector or demod) is a device that performs demodulation, the inverse of modulation.  

A modem (from modulator–demodulator) can perform both operations.

Amplitude Modulation (AM)
Amplitude modulation (AM) is a modulation technique used in electronic communication, most commonly for transmitting information via a radio carrier wave. In amplitude modulation, the amplitude (signal strength) of the carrier wave is varied in proportion to the waveform being transmitted.

Figure: Amplitude Modulation 

Frequency Modulation (FM)
In telecommunications and signal processing, frequency modulation (FM) is the encoding of information in a carrier wave by varying the instantaneous frequency of the wave. 

Frequency modulation is widely used for FM radio broadcasting. It is also used in telemetry, radar, seismic prospecting. In radio transmission, an advantage of frequency modulation is that it has a larger signal-to-noise ratio and therefore rejects radio frequency interference better than an equal power amplitude modulation (AM) signal. For this reason, most music is broadcast over FM radio.

Figure: Frequency Modulation 

Phase Modulation (PM)
Phase modulation (PM) is a modulation pattern that encodes information as variations in the instantaneous phase of a carrier wave.

Phase modulation is widely used for transmitting radio waves and is an integral part of many digital transmission coding schemes that underlie a wide range of technologies like WiFi, GSM and satellite television.

Phase modulation is closely related to frequency modulation (FM); it is often used as an intermediate step to achieve FM. Mathematically both phase and frequency modulation can be considered a special case of quadrature amplitude modulation (QAM).

Figure: Phase Modulation 

Antenna Terminiology: Antenna Noise Temperature, Directivity, Antenna Gain

Antenna Noise Temperature: It is the measure of all the external noise collected by a receiving antenna. Measured in Kelvin (K). It varies with antenna diameter, elevation angle and antenna polarisation. The larger the antenna, the lower the noise temperature. Major noise sources are cosmic noise (caused due to sun, moon and starts) and ground noise; caused due to noise energy radiated from the soil. 

Antenna Directivity
Directivity is a fundamental antenna parameter. It is a measure of how 'directional' an antenna's radiation pattern is. An antenna that radiates equally in all directions would have effectively zero directionality, and the directivity of this type of antenna would be 1 (or 0 dB).

Silly side note: When directivity is specified for an antenna, what is meant is 'peak directivity'. Directivity is technically a function of angle, but the angular variation is described by its radiation pattern. 

Antenna Gain
The term Antenna Gain describes how much power is transmitted in the direction of peak radiation to the power that would be radiated in the same direction by an isotropic antenna. Antenna gain is more commonly quoted than directivity in an antenna's specification sheet because it takes into account the actual losses that occur.

A transmitting antenna with a gain of 3 dB means that the power received far from the antenna will be 3 dB higher (twice as much) than what would be received from a lossless isotropic antenna with the same input power. Note that a lossless antenna would be an antenna with an  antenna efficiency of 0 dB (or 100%). Similarly, a receive antenna with a gain of 3 dB in a particular direction would receive 3 dB more power than a lossless isotropic antenna. The gain figure is only applicable to a particular direction and frequency. 

Abbreviation Used in Satellite Communication

AFC --- Automatic Frequency Control
AFD --- Active Format Description
ALC --- Automatic Loudness/Level Control
AM ---- Amplitude Modulation
AOV --- Angle of View
APID --- Audio Payload Identifier 
APSK --- Amplitude and Phase-Shift Keying or Asymmetric Phase-Shift     keying 
ASI --- Asynchronous standard interface  or   Asynchronous serial interface

ATSC --- Advanced Television System Committee.
ATM --- Asynchronous Transfer Mode

AVC --- Advanced Video Coding
AVP ---  Advanced Video Processor 
BISS --- Basic Interoperable Scrambling System
BPSK --- Binary Phase Shift Keying 
BSS --- Broadcast Satellite Service
BW --- Bandwidth
C&D --- Contribution & Distribution 
CA --- Conditional Access
CAM --- Conditional Access Module 
CAS ---Conditional Access System
CAT --- Conditional Access Table 
CBER --- Convolutional Bit Error Rate / Channel Bit Error Rate
CBR --- Constant Bit Rate
CCW --- Counter Clock Wise
CDP --- Cisco Discovery Protocol
CNR --- Carrier to Noise Ratio
CPI --- Cross Polarization Isolation
CSM --- Control Status Message
DMS --- Digital Monitization System
DPCM --- Differential Pulse Code Modulation
DPSK --- Differential Phase Shift Keying
DQPSK --- Differential Quadrature Phase Shift Keying
DSB --- Direct Satellite Broadcast
DSM --- Device Status Message
DSNG --- Satellite News Gathering
DSS --- Digital Satellite System
DTH --- Direct To Home
DTTV --- Digital Terrestrial Television 
DVB --- Digital Video Broadcast
DVB-S --- Digital Video Broadcasting — Satellite
DVB-S2 --- Digital Video Broadcasting — Satellite — Second Generation 
ECC --- Error Correction Code.
ECMG --- Entitlement Control Message Generator 
EDH --- Error Detection and Handling
EDTV --- Enhanced/Extended Definition TV
EIRP --- Effective Isotropic Radiated Power OR  Equivalent Isotropic Radiated Power 
EIS --- Event Information Scheduler 
EMMG --- Entitlement Message Manager Generator 
ENG --- Electronic News Gathering
EPG --- Electronic Program Guide 
ETSI --- European Telecommunications Standards Institute
EVE --- Ericsson Virtualized Encoding 
FEC --- Forward Error Correction
FGM --- Fixed Gain Mode
FM --- Frequency Modulation
FSS --- Fixed Service Satellite
FTA --- Free to Air
GMT --- Greenwich Mean Time
GPS --- Global Positioning System
GUI  --- Graphical User Interface
HPBW --- High Power Beam Width
Hsync --- Horizontal Sync
IF --- Intermediate Frequency
IGMP --- Internet Group Management Protocol
LA --- Lighting Arrester
LHCP --- Left Hand Circular Polarization
LKM --- Link Margin
LM --- Link Margin 
LNA --- Low Noise Amplifier
LNB --- Low Noise Block downconverte
LNC --- Low Noise Converter
LO --- Local Oscillator
LTC --- Longitudinal Time Code
LV --- Laser Vision
MCPC --- Multiple Channel Per Carrier
MCTRF --– Motion Compensated Recursive Temporal Filtering
MER --- Modulation Error Rate
MGP --- Multicast Guard Protocol
MHEG --- Multimedia and Hypermedia Experts Group
MPE --- Multiprotocol Encapsulation
MPTS --- Multiple Program Transport Streams
MSM --- Multicast Status Message
MSps --- Mega Symbols per second
MSS --- Mobile Satellite Service
MVP --- Multiscreen Video Processing

NF --- Noise Figure  
OAC --- Over - air control 
OOK --- On Off Keying
PAA --- Phase Aligned Audio
PAT --- Program Association Table 
PCR --- Program Clock Reference
PCR PID ---  Program Clock Reference  Packet Identifier
PDG --- Private Data Generator 
PIN --- Personal Identification Number
PING --- Packet INternet Groper
PLL --- Phase Locked Loop
PLR --- Program Level Redundency 
PM --- Phase Modulation
PSI --- Program specefic Information 
PSIG --- Program Specefic Information Generator 
PSIP --- Program and System information Protocol 
PSK --- Phase Shift Keying
PVST --- Per-VLAN Spanning Tree
PWM --- Pulse Width Modulation
QAM --- Quadrature Amplitude Modulation
QPSK --- Quadrature Phase Shift Keying
RAI --- Random Access Indicator
RF --- Radio Frequency
RSS --- Receive Side Scaling
RX --- Receive
SBCA --- Satellite Broadcasting and Communications Association
SCPC --- Signal Channel Per Carrier
SCS --- SimulCrypt Synchronizer
SFN --- Single Freuency Network 
SHF --- Super High Frequency
SI --- Service Information
SMPTE --- Society of Motion Picture & Television Engineers
SNG --- Satellite News Gathering
SNMP --- Simple Network Management Protocol  
SNR --- Signal to Noise Ratio
SPG --- Sync Pulse Generator
SPTS --- Single Program Transport Streams
SSM --- Source Specefic Multicast 
SSPA --- Solid State Power Amplifier
SST --- Single Sideband Transmission
STB --- Set Top Box
STT --- System Time Table 
TC --- Time Code
TDM ---Tendburg Device Manager / Time Division Multiplexing
TDT --- Time and Date Table
TOT --- Time Offset Table
TWT --– Ttraveling Wave Tube 
TX --- Transmission
UHF --- Ultra High Frequency
UID --- Unique Identifier
UPS --- Uninterrupted Power Supply
UWB --- Ultra Wide Band
VAS---  Value Added Service
VCM  --- Video Coding Module
VE --- Virtual Ethernet 
VHF --- Very High Frequency
VION --- Virtual Input/Output Nodes 
VITC --- Vertical Interval Time Code
VPC --- Video Procesor Chassis
VPID --- Video Payload Identifier 
VSAT --- Very Small Aperture Terminal
VSWR --- Voltage Standing Wave Ratio
VTP --- VLAN Trabnking Protocol 
VTY --- Virtual Terminal Interface