VSAT(VERY SMALL APERTURE TERMINALS(

Prepared by/fata el hoorVSAT ((very small aperture terminal))

VSAT

In this powerpoint we aim to

• Describe the technology of VSAT

• Planning process and its topology

• BANDS OF VSAT

WHAT IS VSAT!

VSAT is micro_earth station that uses the latest innovations in the field of satellite communication to allow user’s access to reliable satellite communication .

It is provide users with simple equipment that required minimal installation and repair easy to repair and simple to troubleshoot.

VSAT STATION IN DETAILS

OVERALL VIEW ON VSAT STATION

ODU&antenna provide RF conversion and amplification for the satellite downlink &uplink

ODU called transceiver In up link we use(up converter + SSPA) In down link we use (LNA & down converter) IDU provide modulation & demodulation From IDU we can obtain service we need (data-

telephone-fax)

ODU UNITAs depicted in figure We can see ODU unit !!

IDU UNIT

IDU FRONT VIEW IDU BACKWARD VIEW

LOW POWER CONSUMING

it is excited that you know we need low power in some cases solar cellProviding power,

Simplicity in VSAT installation It takes only few hours

VSAT terminal is apart of network with LARGER earth station that serves as network The hub contain the intelligence to control network operation configuration and traffic each VSAT terminal .Database generated by the hub are else used for billing purpose

HUB IN DETAIL

VSAT RELIABLE SERVICE

VSAT technology often high availability & reliability it is accuracy reaches to 99.6 to 99.7percentage For the total VSAT network. BER(bit error rate) is better than 1error in 10 million transmitted bits

RELATION BETWEEN VSAT&HUB

TWO TYPES IN COMPARISON!

TERRESTRIAL VSAT

TWO TYPES IN COMPARISON!

TERRESTRIAL VSAT

The cost per lease line increase with distance between headquarter

It exposed to cable connection break

Installation fee is related to the required data rate

Long distance not apply to VSAT

VSAT can be managed independently of terrestrial network

The equipment and installation costs VSAT higher than terrestrial alternatives

COST OF EACH OTHER

TERRESTRIALVSAT

Cost of dedicated lines Monthly

maintenance=……$ Installation fee(non

recurring)=………$ Equipment

charges=……$ Service charges=…..$

Cost of VSAT service Service charges=….$ VSAT equipment

cost=….$ Installation fee(non

recurring)=……$

COST OF TERRESTRIAL & VSAT IN PLOT

VSAT ADVANTAGES MORE AND MORE! In addition to low

cost Full control over the

entire communication network

In sensivity to distance between nodes

High grade of service and flexibility

VSAT TOPOLOGY NETWORK

We commonly use mesh &star topology in VSAT network in star topology each VSAT transceiver only to the hub . This isn't preclude VSAT terminals from communication

among themselves as vsat communication is routing through hub by using two satellite hop.

Majority of VSAT use star topology because the large antenna gain at the hub optimizes the use of space segment and minimize the size of the VSAT terminal.

The drawback of star topology is the delay for VSAT to VSAT communication as we take two hops

STAR &MESH TOPOLOGY

MESH TOPOLOGY

In mesh topology allow terminals to communicate each other directly ,hub controlled communication and tears down processes ,hub not involved it in carrying traffic it said operate hublessly it suited for voice that cannot tolerate delay.

VSAT terminals is equipped with the network management and control equipment each VSAT must have sufficient power and receive sensivity (G/T) to communicate with every other VSAT .

Mesh topology requires larger antennas and SSPAs than star topology

VSAT BANDS

Currently we use two frequency bandsC-band and Ku-Band.

For C-band operations, the antennas transmit at 6 GHz and receive at 4 GHz.

Ku-band requires transmission at 14 GHz and reception at 11-12 GHz

WHICH FREQUENCY BAND IS BETTER!

TABLE 1-1. KU-BAND VS. C-BAND

There is no direct answer to this question. The VSAT operator mustdecide the frequency band based on each band’s different aspectslisted in Table 1-1

Proper network engineering can minimize the effects of Ku-band signalfading during rain. High network availability is available at both Ku- and Cband.VSAT operators prefer Ku-band to C-band because it allows them toreduce the capital investment by using smaller antennas