Sc Lab Manual

7/30/2019 Sc Lab Manual

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LAB MANUAL

OF SATELLITE

COMMUNICATION

Submitted by

Ishita aggarwal

Lecturer ECE


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Experiment 1

Objective:Changing different combinations of uplink

and downlink frequencies and to checkthe

communication link

Equipments Needed:1. UplinkTransmitter

2. Dish Antennas

3. DownlinkReceiver

4. Connecting cables.

5. Satellite Transponder

6. Audio/Video input (VCD)

7. Monitor (TV monitor)

Procedure:

1. Connect the Satellite Uplink transmitter to AC Mains.

2. Switch ON the transmitter and frequency displaywill come on.

3. The transmitting frequency can be selected by

Frequency Select switch. The frequency can be

changed from 2450-2468 MHz.

4. Connect Dish Antenna to Uplink transmitter withBNC -BNC lead.

5. Place Downlink Receiver at a convenient distance of5-7m. (It can go even up to10m.).

6. Place a Satellite Transponder betweenTransmitter and Receiver at a convenient

distance; preferably all three can be placed in

equidistant triangle of distance 5-7m.

7. Connect the Satellite Transponder to the AC

Mains and switch it ON by mains switch.

8. Connect the Downlink Receiver to the AC


9. The Downlink Receiver Frequency can be changed

from 2414-2432 MHz.

10. Attach Dish Antenna to the Downlink receiver with

BNC - BNC lead.

11. Align both the Transmitter and Receiver Antenna's in

line.

12. Adjust transmitter uplink frequency to 2468

MHz and transponder receiver frequency also

to 2468 MHz

13. Keep Downlink Frequency of Transponder to 2414


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MHz.

14. Keep the Downlink Receiver to 2414 MHz.

15. Connect the Audio/Video signal at the input

socket provided on the UplinkTransmitter, Video atvideo input and audio at either Audio-I or Audio-II

input.

16. Connect TV monitor to the Audio/Video output

of Downlink receiver. (Video from Video Output,

audio from Audio-I or Audio-II output (as intransmitter)) Set TV in AVMode.

17. To watch Video signal toggle the switch

provided at Transponder unit to the Videoposition.

18. The TV monitor will display video and audio

signal that you have connected to uplink Transmitter

input.

19. Now change uplink-transmitting frequency

from 2468 to 2450 MHz and correspondingly the

receiver frequency of transponder is to be changed

to 2450 MHz you will receive the same quality ofsignal at the output of the

downlinkreceiver.

20. Now change the downlink frequency of

transponder from 2414 to 2432 MHz and similarly

change downlink receiver tuning frequency to 2432

MHz you will be receiving the same quality ofsignal.

R

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:

The above experiment shows a successful establishment

of satellite audio/video link between Uplink transmitter

and Downlink receiver at different up-link and down-link

frequencies.


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Experiment 2

Objective:

To set up a active and passive satellite communication link and

study their difference.

Equipments Needed: 1. Uplink Transmitter2. Dish Antennas3.Downlink Receiver4. Connecting cables. 5. Satellite

Transponder

Theory: Passive Satellites: Passive Satellites are the Satellites

that simply reflect a signal back to earth; there are no gain

devices on board to amplify the signal. An advantage being thatthey do not require sophisticated electronic equipment on board,

although they are not necessarily void of power. Some passive

Satellite requires a radio beacon transmitter for tracking &ranging purpose. A beacon is a continuously transmitted

unmodulated carrier that an earth station can lock onto and use toalign its antennas or to determine the exact

location of the Satellite. A disadvantage is there in using thesedue to inefficient use of

transmitted power.

Active Satellites:

Active Satellites are the Satellites that electronically repeat the

signal and send it backto earth. It receives, amplifies, and retransmits the signal. The

communication


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capability of active systems with "the directional antennas

rapidly becomes muchgreater than that of the passive system as the altitude is

increased. The Uplink Transmitter sends signals at an Uplink

frequency, which is higher than downlink frequency to avoid the

interference. The quality of signal is much improved with activesatellite especially when distances between transmitter and

receiver are considerable.

Procedure:

Active satellite


2. Switch ON the transmitter and frequency display will come

on.

3. The transmitting frequency can be selected by Frequency

Select switch. The

frequency can be changed from 2450-2468 MHz.

4. Connect Antenna to Uplink transmitter with BNC -BNC lead.

5. Place Downlink Receiver at a convenient distance of 5-7m. (It

can go even up to 10m.).

6. Place a Satellite Transponder between Transmitter and

Receiver at a convenient

distance; preferably all three can be placed in equidistant triangle

of distance 5-7m.

7. Connect the Satellite Transponder to the AC Mains and switch

it ON by mainsswitch.

8. Connect the Downlink Receiver to the AC Mains and switch it

ON by mainsswitch.

9. The Downlink Receiver Frequency can be changed from

2414-2432 MHz.

10. Attach Antenna to the Downlink receiver with BNC - BNC

lead.

11. Align both the Transmitter and Receiver Antenna's in line.


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12. Adjust transmitter uplink frequency to 2468 MHz and

Transponder receiver

frequency also to 2468 MHz, from frequency select 1 and

frequency select 2.

13. Keep Downlink frequency of Transponder at 2414 MHz.

14. Keep the Downlink Receiver at 2414 MHz.

15. Now Select Tone from Channel select B in Uplink

Transmitter.

16. Set the Downlink Receiver at speaker mode by changing

Channel Select B.

17.Now we can listen the amplified tone at the receiver.

Passive Satellite



on.

3. The transmitting frequency can be selected by Frequency

Select switch. The

frequency can be changed from 2450-2468 MHz.

4. Connect Antenna to Uplink transmitter with BNC -BNC lead.5. Place Downlink Receiver at a convenient distance of 5-7m. (It

can go even up to 10m.).

6. Connect the Downlink Receiver to the AC Mains and switch it

ON by mains

7. Switch.The Downlink Receiver Frequency has to remain same

as the transmitter frequency.

8.. Attach Antenna to the Downlink receiver with BNC - BNC

lead.


10. Now Select Tone from Channel select B in Uplink

Transmitter.

11. Set the Downlink Receiver at speaker mode by changing

Channel Select B.

12. Now we can listen the unamplified tone(reflected signal) at

the receiver.


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Result:

The above setup shows that a successful satellite communicationlink has been

setup between Transmitter and Receiver in case of active and

passive satellite communication with a difference that the

amplified signal is obtained in case of active satellite.

Experiment 3

Communicating VOICE signal through satellite link

Equipments Needed:

1. Uplink. Transmitter

2. Dish Antennas

3. DownlinkReceiver



6. Microphone

Procedure:


2. Switch ON the transmitter and frequency display

will come on.




4. Connect dish Antenna to Uplink transmitter withBNC -BNC lead.

5. Place Downlink. Receiver at a convenient

distance of 5-7m. (It can go even up to 10m.).

6. Place a Satellite Transponder betweenTransmitter and Receiver at a convenient


equidistant triangle of distance

5

-

7


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m

.



8. Connect the Downlink. Receiver to the ACMains and switch it ON by mains switch.

9. The Downlink. Receiver Frequency can be changed

from 2414-2432 MHz.

10. Attach dish Antenna to the Downlink receiver with

BNC - BNC lead.

11. Align both the Transmitter and Receiver Antenna's inline.


MHz and transponder receiver frequency alsoto 2468MHz.

13. Keep Downlink Frequency of Transponder to

2414MHz.

14. Keep the Downlink Receiver to 2414MHz.

15. Connect microphone input at the socket

marked 'MIC' on the UplinkTransmitter.

16. Select MIC mode from Channel Select B in

Uplinktransmitter.

17. Select the Speaker mode from Channel Select B

in DownlinkReceiver.

18. Speak in the mike and you will hear the same sound

in the speaker ofreceiver.

Result:

The above shows a successful establishment of voice

link between transmitterand receiver.


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Experiment 4

Transmitting and receiving function generator waveformsthrough satellite link

Equipments Needed:

1. UplinkTransmitter2. Dish Antennas

3. DownlinkReceiver



6. Function generator

Procedure:


2. Switch ON the transmitter and frequency displaywill come on.




4. Connect Antenna to Uplink transmitter with BNC-BNC lead.

5. Place Downlink Receiver at a convenient distance of

5-7m. (It can go even up to

10m.).6. Place a Satellite Transponder between

Transmitter and Receiver at a convenient

distance; preferably all three can be placed inequidistant triangle of distance 5-

7m.





9. The Downlink Receiver Frequency can be changedfrom 2414-2432 MHz.

10. The Downlink receiver On-Off toggle

switch will switch On-Off the receiver.

11. Attach Antenna to the Downlink receiver with BNC -

BNC lead.

13. Align both the Transmitter and Receiver Antenna's in

line.




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to 2468MHz.

15. Keep Downlink Frequency of Transponder to

2414MHz.

16. Keep the Downlink Receiver to 2414MHz.

17. Connect function generator Triangular wave

output to Audio-I socket provided on uplink

transmitter.

18. Connect Audio-I socket of downlink receiver to the

Oscilloscope.

19. Feed the signal of 1 KHz Triangular wave andyou will observe similar wave of same frequency

on Oscilloscope.

Result:

Function generator waveforms are successfullyreceived at downlink receiver through satellite

communication link.


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Experiment 5

Establishing a direct communication link between Uplink

Transmitter and Downlink

Receiver using tone signal.(digital baseband signal)

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Procedure:



on.


frequency select switch. The frequency can be changed

from 2450-2468 MHz

4. Connect Antenna to Uplink transmitter with BNC -BNC lead.

5. Place Downlink Receiver at a convenient distance of 5 -

7m. (It can go even up to 10m.).

6. Connect the Downlink Receiver to the AC Mains and

switch it ON by mains switch.

7. The Downlink Receiver Frequency can also be changed from2414-2432 MHz

8. Attach Antenna to the Downlink receiver with BNC - BNC

lead.



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10. Keep the Uplink transmitter and Downlink receiver

frequency to the same frequency.

11. Now Select the Tone from Channel Select B, so as

to transmit tone signal from Uplinktransmitter.

12The Tone signal is switched to Audio II of transmitter andtransmitted.

13. Make the Downlink Receiver in Speaker mode with

the help of Channel

Select B

14. To observe Tone Signal on CRO select Tone mode from

the Channel SelectB.

15. Connect CRO probes to received tone socket.

16. By changing the frequency and amplitude observe the

received tone on CRO as well asonspeaker.

Result:

A clear music indicates that the microwave link

has been successfully setup between uplink

transmitter and down link receiverdirectly.

Experiment 6

Transmitting and receiving PC data through satellite link

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Procedure:


2. Switch ON the transmitter by Mains switch

and frequency display will light up.




4. Connect Antenna to Uplink transmitter with BNC-BNC lead.


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10m.).

6. Place a Satellite Transponder between


distance; preferably all three can be placed inequidistant triangle of distance

5-7m.





9. The Downlink Receiver Frequency can be changedfrom 2414-2432 MHz.

10. Attach Antenna to the Downlink receiver with BNC -BNC lead.

11. Align both the Transmitter and Receiver

Antenna's in line such that both are in parallel

alignment.





to 2468 MHz.


MHz.

15. Keep the Downlink Receiver to 2414 MHz.16. Switch ON the PC's and install software.

17. Connect interfacing cable from USB port of uplinktransmitter to first PC.

18. Connect the interfacing cable from USB port of

Downlink receiver to 2nd

PC.

19. Install the drivers so that USB device is detected.

20. Now Select appropriate communication port and

Baud Rate (19200) on both


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PC's.

21. To watch PC Data toggle the switch provided at

Transponder unit to the Video position.

22. Select 1st

PC as transmitter and 2nd

PC as a receiver

on the software window.

23. When the link is established, the typed matter

on first PC will be received to second PC via

Satellite link.

Result:

PC data transmitted from first PC is received in

the second PC via Satellite link.

Experiment 7

To calculate signal to noise ratio of established satellite

link

Equipments Needed:

1. UplinkTransmitter

2. Dish Antennas


4. DownlinkReceiver

5. CRO Connecting cables.

Procedure:





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4. Connect Antenna to Uplink transmitter with BNC

-BNC lead.5. Place Downlink Receiver at a convenient distance of


10m.).




equidistant triangle of distance 5-

7m.






from 2414-2432 MHz.



Antenna's in line, such that both are in parallel

alignment.12. Adjust transmitter uplink frequency to 2468


to 2468 MHz.

13. Keep Downlink Frequency of Transponder to 2414MHz.


15. Now Select the Tone from Channel Select B,

so as to transmit tone signal from Uplink

transmitter.

16. Make the Downlink Receiver in Tone mode with

the help of Channel Select


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B.

17. Observe Tone Signal on CRO and measure its

amplitude. (The received tone has original signal

and noise both, say it S1 ).

18. Now change Tone mode to any other modewith the help of Channel Select B of the

uplink transmitter and again measure amplitude

of received signal at downlink receiver (This

signal have only noise, say it N).

19. Now subtract amplitude of noise from previously

received signal (Tone +

noise), you can get actual

tone signal amplitude (say it

S). S = S1 N

20. Calculate signal to noiseratio from the formula.

Signal to noise ratio = S /NSignal to noise ratio (in dB) = 20 log S /N

Result:

Signal to

noise ratio

(in numeric)

=_

Signal to

noise ratio

(in dB) =_

__dB


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Experiment 7

Study the delay between Uplink transmitter and

Downlink receiver during data transmission.

Equipments Needed:


2. Dish Antennas

3. DownlinkReceiver


5. Digital Storage Oscilloscope


Procedure:








-BNC lead.

5. Place Downlink Receiver at a convenient distance of5-7m. (It can go even up to

10m.).



distance; preferably all three can be placed inequidistant triangle of distance

5-7m.






from 2414-2432 MHz.



24/40



alignment.



to 2468 MHz.


MHz.


15. Select Data mode in the uplink transmitter using

Channel Select A.

16. Select Data mode in the downlink receiver usingChannel select A.

17. To observe data from data generator, toggle the

switch provided at Transponder unit tothe

Telemetryposition.

18. Connect the DSO to Received Data section and

observe the data.

19. The recommended DSO settings are as follows:

l Adjust the Time/Div knob at 50ms.

l Adjust Volt/Div. Knob at 2V.

l Set appropriate trigger level, so that the signal

becomes stable on screen.

20. Now slightly move the Delay Adjust knob andobserve the changes in the Data stream onDSO.

Result:

The experiment can be useful to observe simulated delayin satellite.


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Experiment 8(a)

To send tele-command and receive intensity of light fromsatellite

Equipments Needed:

1. UplinkTransmitter2. Dish Antennas

3. DownlinkReceiver


5. Connecting cables

Procedure:

1.Connect the Satellite Uplink transmitter to AC Mains.

2.Switch ON the transmitter by Mains switch and

frequency display will light up.

3.The transmitting frequency can be selected by

Frequency Select switch. The frequency can be changed

from 2450-2468 MHz.

4.Connect Antenna to Uplink transmitter with BNC -BNC lead.

5.Place Downlink Receiver at a convenient distance of 5-7m. (Itcan go even up to

10m.).

6.Place a Satellite Transponder between Transmitter and

Receiver at a convenient distance; preferably all three canbe placed in equidistant triangle of distance 5-

7m.

7.Connect the Satellite Transponder to the AC Mains and


8.Connect the Downlink Receiver to the AC Mains and


9.The Downlink Receiver Frequency can be changed

from 2414-2432 MHz. Attach Antenna to the

Downlink receiver with BNC - BNC lead.Align both

the Transmitter and Receiver Antenna's in line such

that both are in parallel alignment.

10.Adjust transmitter uplink frequency to 2468 MHzand transponder receiverfrequency also to 2468 MHz.

11.Keep Downlink Frequency of

Transponder to 2414 MHz. Keep the

Downlink Receiver to 2414 MHz.


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Select Tele mode in uplink transmitter and downlink

receiver using Channel select A.

The telemetry section has three toggle switches indicated E

for enable, A1& A0 for selecting Light intensity and

Temperature respectively. The command for light

intensity is 6.

12.In uplink Transmitter switch on the toggle E so that

telemetry becomes enable. Now toggle On A1 and

toggle Off A0 for Light Intensity and do same set-

up fordownlin

k

receiver.

To watch telemetry signal toggle the switch provided at

Transponder unit to the Telemetryposition.

You will find that the intensity of light in percentageform is appearing on the

LCD screen of

downlinkreceiver.

Change the intensity of light manually by using any light

source on transponder, the same ratio of percentage will

appear on the LCD screen.

Result:

As you send tele-command for light intensity, thetransponder starts sending status of light intensity to

the receiver.


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Experiment 8(b)

To send tele-command and receive Temperature from

satellite

Equipments Needed:


2. Dish Antennas

3. DownlinkReceiver


5. Connecting cables

Procedure:








-BNC lead.



10m.).6. Place a Satellite Transponder between



equidistant triangle of distance

5-7m.






from 2414-2432 MHz.

10. Attach Antenna to the Downlink receiver with BNC -

BNC lead.



alignment.



to 2468 MHz.


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Scientech Technologies Pvt. Ltd.

90

ST2272A

13. Keep Downlink Frequency of Transponder to 2414MHz.


15. Select Tele mode in uplink transmitter and

downlink receiver using Channel select A.

16. The telemetry section has three toggle switches

indicated E for enable, A1 & A0 for selecting

Light intensity and Temperature respectively.

17. In uplink Transmitter switch on the toggle E so thattelemetry becomes enable.

18. Now toggle On A0 and toggle Off A1 for

Temperature and do same set-up for downlink

receiver. The tele command for temperature is 5.

19. To watch telemetry data toggle the switch providedat Transponder unit to the

Telemetryposition.

20. You will find that the Temperature of transponder

is appearing on the LCD

screen ofreceiver.

Result:

As you send tele-command for temperature, the

transponder starts sending status oftemperature to the

receiver.


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Theory:

The Uplink Transmitter sends signals at an Uplink

frequency, which is higher than downlink frequency

to avoid the interference. The quality of signal ismuch improved with active satellite especially when

distances between transmitter and receiver are

considerable.

P

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:

1. Connect the SatelliteUplink transmitter to AC

Mains.

2. Switch ON the transmitter and

frequency display will come on.


Frequency Select switch. The frequency can bechanged from 2450-2468 MHz.

4. Connect Antenna to Uplinktransmitter with BNC BNC lead.

5. Place Downlink Receiver at a convenient

distance of 5-7m. (It can go even up to10m.).

6. Place a Satellite Transponder between Transmitter

and Receiver at a convenient distance;

preferably all three can be placed in equidistant

triangle of distance 5-

7m.


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7. Connect the Satellite Transponder to the AC Mains

and switch it ON by mains switch.



9. The Downlink Receiver Frequency can be

changed from 2414-2432 .

10. Attach Antenna to the Downlinkreceiver with BNC - BNC lead.

11. Align both the Transmitterand Receiver Antenna's in

line.


MHz and Transponder receiver frequency also to

2468 MHz, from frequency select 1 and frequency

select 2. 13Keep Downlink frequency of Transponder

at 2414 MHz.

14. Keep the

Downlink Receiver

at 2414 MHz.

15. Now Select Tone from Channelselect B in UplinkTransmitter.

16. Set the Downlink Receiver at speaker modeby changing Channel Select B.

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o

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By switching Off the Power of SatelliteTransponder, you can demonstrate a Link Fail

operation.

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The above setup shows that a successful satellite

communication link has been setup between

Transmitter and Receiver.

The link failure operation can be

understood from theprocedure.


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Experiment 10

Establishing an Audio-Video satellite link between

Transmitter and Receiver

Equipments Needed:

1) UplinkTransmitter

2) Dish Antennas

3) DownlinkReceiver

4) Connecting cables

5) Satellite Transponder

6) Audio/ Video input (VCD)

7) Monitor (TV monitor)

Procedure:

1. Connect the Uplink Transmitter to the AC





3. Connect dish Antenna to Uplink transmitter with

BNC -BNC lead.


5-7m. (It can go even up to10m.).




equidistant triangle of distance 5-

7m.

6. Connect the Satellite Transponder to the ACMains and switch it On by mains switch.




from 2414-2432 MHz.

9. Attach dish Antenna to the Downlink receiver with

BNC - BNC lead.

10. Align both the Transmitter and Receiver Antenna's inline.



to 2468 MHz.


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MHz.



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14. Connect the Audio/Video signal at the input socket provided on theUplink

Transmitter, Video at video input and audio at either Audio-I or Audio-II

input.

15. To watch Video signal toggle the switch provided at Transponder unit to

the

Videoposition.

16. Connect TV monitor to the Audio/Video output of Downlink receiver.

(Video from Video Output, audio from Audio-I or Audio-II output (as in

transmitter)) Set TV in AVMode.

17. The TV monitor will display video and audio signal that you have connectedto

Uplink Transmitterinput.

18. Try link fail by using TransponderOFF.

Result:

The monitor display shows that a successful audio and video link has

been establish between Transmitter and Receiver through satellite.


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