Jurnal E-Komtek Vol.
No.
https://jurnal.
politeknik-kebumen.
id/index.
php/E-KOMTEK p-ISSN : 2580-3719 e-ISSN : 2622-3066 The Simulation of Very High Frequency (VHF) Voice Communications at Aeronautical Mobile Satellite (Rout.
Service (AMS(R)S) AA Kompiyang Karmana Putra .
Muhammad Suryanegara Department of Electrical Engineering.
Indonesia of University.
Indonesia, 16424 kompiyang@ui.
https://doi.
org/10.
37339/e-komtek.
Published by Politeknik Piksi Ganesha Indonesia Artikel Info Submitted:
09-05-2023
Revised:
05-06-2023
Accepted:
05-06-2023
Online first :
28-06-2023
Abstract To expand the coverage of current aviation VHF communication services, it is necessary to develop a satellite-based VHF communication system.
This research aims to analyze the satellite link budget calculations for VHF AMS(R)S frequencies using a Low Earth Orbit (LEO) satellite at an altitude of 600 km, in accordance with the studies conducted by ICAO and ITU.
The link budget calculation, using parameters such as aircraft antenna gain = -1 dBi, satellite antenna gain = 8 dBi.
RF power of the aircraft = 16 watts, and RF power of the satellite = 85 watts, results in satellite receiver sensitivity between -107 dBm - 25.
56 dB, as well as aircraft receiver sensitivity between -93 dBm - 38.
65 dB.
When simulating an end-to-end link budget .
oopback: aircraft-satellite-aircraft between 14.
92 dB - 14 dB.
Simulations were also carried out for voice communication using an AWGN channel illustration with an Eb/No of 10 dB, resulting in the performance of the VHF audio link.
Keywords: Information Systems.
Petty Cash.
Waterfall.
UML Abstrak Untuk memperluas cakupan layanan komunikasi VHF penerbangan saat ini, perlu dikembangkan sistem komunikasi VHF berbasis satelit.
Penelitian ini bertujuan untuk menganalisa perhitungan link budget satelit untuk frekuensi VHF AMS(R)S dengan menggunakan satelit Low Earth Orbit (LEO) pada ketinggian 600 km, sesuai dengan studi yang dilakukan oleh ICAO dan ITU.
Perhitungan link budget, dengan menggunakan parameter seperti gain antena pesawat = -1 dBi, gain antena satelit = 8 dBi, daya RF pesawat = 16 watt, dan daya RF satelit = 85 watt, menghasilkan sensitivitas receiver satelit antara -107 dBm - 25,56 dB, serta sensitivitas receiver pesawat antara -93 dBm - 38,65 dB.
Saat simulasi link budget end-to-end .
oopback: pesawat-satelit-pesawat antara 14,92 dB 14 dB.
Simulasi juga dilakukan untuk komunikasi suara dengan menggunakan ilustrasi kanal AWGN dengan Eb/No sebesar 10 dB, sehingga menghasilkan performansi link audio VHF.
Kata-kata kunci: AMS(R)S.
VHF.
ICAO.
Link Budget Satelit.
C/N.
Eb/No.
BER.
This work is licensed under a Creative Commons Attribution-NonCommercial 4.
International License.
A AA Kompiyang Karmana Putra.
Muhammad Suryanegara Introduction International Civil Aviation Organization (ICAO) sets standards, procedures, principles, and technical requirements for air navigation and civil aviation organizations to ensure safety, security, and future technological advancements .
One of the protocol standards established is the communication standard between aircraft pilots and Air Traffic Controllers (ATC) using the Very High Frequency (VHF) communication system known as the air band.
This system is used for voice and data communication, utilizing frequency allocation between 118 to 137 MHz.
Until now, the VHF communication system has been used mainly for limited ground communication or air-to-ground communication.
As a result, the network still needs to cover areas such as remote regions over the oceans.
Therefore.
ICAO and ITU (International Telecommunication Unio.
are considering implementing the VHF communication system for the Aeronautical Mobile Satellite (Rout.
Service (AMS(R)S) .
AMS(R)S is a satellite-based communication service for aviation.
It enables pilots to communicate with ATC and other aircraft pilots using voice and data communication.
AMS(R)S
is designed to provide reliable and secure communication services for air traffic management, including air traffic control, flight information, and meteorological services.
AMS(R)S is a critical component of modern air traffic management as it allows real-time communication between pilots and ground controllers, enhancing air transportation safety and efficiency.
It operates on specific frequency bands regulated by ITU and ICAO.
Based on the distance calculations, the AMS(R)S system that can support VHF aviation communication is a Low Earth Orbit (LEO) satellite with an orbit altitude of 600 km.
The communication delay is approximately 4 ms at the closest point and 18.
9 ms at the farthest point.
These delays do not significantly impact the quality of aviation communication services.
This research aims to review and analyze the satellite link budget calculations for the AMS(R)S communication system using the frequency allocation of 118 - 137 MHz (VHF), per the studies conducted by ITU and ICAO.
The research considers that there are no changes in the VHF communication system devices on aircraft, both for voice and data communication.
Additionally, the research aims to create a simulation of voice communication using the Mathematical Programming Language.
The link budget calculations that will be analyzed focus solely on the communication link between the aircraft and the AMS(R)S satellite in both The feeder link from the AMS(R)S satellite to the ground station connected to ATC A AA Kompiyang Karmana Putra.
Muhammad Suryanegara will not be discussed, as it is assumed to utilize fixed satellite services (FSS) operating in specific Satcom bands such as L-Band.
C-Band.
Ku-Band, or K/Ka-Band, as shown in Figure 1.
Figure 1.
The Concept of the AMS(R)S - VHF Satellite Communication System Method The satellite link budget calculation The satellite link budget calculation is a process that determines the power and signal quality required at each end of the satellite communication link to achieve the desired performance level.
The link budget calculation considers various factors of losses and gains within the system, including transmission losses .
ath losse.
, antenna gains, atmospheric attenuation, and other factors that affect the strength and quality of the signal.
Here are the factors to consider in satellite link budget calculations:
The effective distance .
lant rang.
between an aircraft and a satellite The effective distance .
lant rang.
between an aircraft and a satellite depends on various factors, including the satellite's altitude and the changing positions of both the satellite and the aircraft.
Determining the maximum distance for satellite operations is crucial for evaluating system performance and plays a vital role in the overall architecture design.
Illustrate the position of the aircraft relative to the AMS(R)S-VHF satellite is presented on Figure 2.
Figure 2.
Illustration of the aircraft's position relative to the AMS(R)S satellite.
A AA Kompiyang Karmana Putra.
Muhammad Suryanegara The satellite uplink .
ircraft to AMS(R)S) link budget calculation After obtaining the calculation of the effective distance .
lant rang.
between the aircraft and the satellite, the next step is to perform the satellite uplink link budget calculation from the aircraft to the satellite.
According to ICAO regulations, the development of VHF communication via AMS(R)S should not involve any changes to the VHF transmission equipment on the aircraft.
Therefore, the uplink link budget calculation aims to determine the received power at the satellite, which provides the sensitivity value for the AMS(R)S satellite receiver device.
The following is the formula for calculating the received power level on the satellite side:
cEycIycu ] = .
ayaycIycE] Oe .
aycIy.
Oe .
cIy.
Oe .
cEy.
Oe .
ayaycIycu ] .
aycIycu ] yccyaAycO In this formula, the transmitted power refers to the power transmitted by the aircraft's VHF transmitter, and the gains and losses account for factors such as antenna gains, path loss, cable losses, atmospheric attenuation, and other miscellaneous losses.
The sensitivity requirements for the AMS(R)S satellite receiver can be determined by calculating the received power.
EIRP (Effective Isotropic Radiated Powe.
is the total power transmitted from the transmitter .
cEycNycu ] that is amplified by the antenna gain .
aycNycu ] and reduced by the losses in the transmitter channel .
eeder los.
aya ycNycu ] .
In formula form, the EIRP can be calculated as:
ayaycIycE] = .
cEycNycu ] .
aycNycu ] Oe .
aya ycNycu ] yccyaAycO Electromagnetic signals propagating through space experience losses due to attenuation, known as Free Space Losses (FSL).
FSL refers to the power loss that occurs when electromagnetic signals pass through free space without obstacles or external interference.
The formula for calculating Free Space Loss (FSL) in satellite link budget calculations is as follows .
aycIy.
= 32,4 20 ycoycuyci ycoycuyci .
20 ycoycuyci ycoycuyci .
d = the distance between transmitter and receiver .
f = operating frequency (MH.
SL (Scintillation Losse.
are losses that occur in the ionospheric layer and have a significant impact on VHF frequencies.
The influence of SL related to geometric positioning is determined using the recommendations of the Global Ionospheric Scintillation Model, as per Recommendation ITU-R P.
531-14 .
In this research, the value of SL is set at 5 dB by the ITU PL (Polarization Losse.
occur due to electromagnetic signals passing through a magnetic field.
In this link budget calculation.
PL is determined to be 3 dB by the ITU-R P.
53114 recommendation .
A AA Kompiyang Karmana Putra.
Muhammad Suryanegara To determine the performance of a link, it is necessary to calculate the Carrier to Noise Ratio (C/N).
The calculation of C/N for the uplink can be done using the formula .
a/ycAycycy ] = .
ayaycIycE] Oe .
aycIy.
Oe .
cIy.
Oe .
cEy.
Oe .
ayaycIycu ] .
cN ] Oe .
Oe yaAycO
G/T
: Gain to Noise Temperature at the receiver .
B/ oK) : Constant of Boltzmann = -228,6 dBW/oK.
: Bandwidth (H.
The satellite downlink (AMS(R)S to aircraf.
link budget calculation The calculation of the satellite downlink link budget from the satellite to the aircraft is performed to determine the required RF transmit power from the satellite so that the receiving device in the aircraft can receive the signal with the desired performance as per the regulations of ITU and ICAO.
The sensitivity of the receiving device on the aircraft is set to -90 dBm or Power Flux Density (PFD) on the aircraft = -116,2 dBW/m2 .
The link budget calculation considers various factors such as path loss, antenna gain, and atmospheric losses SL's influence ensures that the received signal power at the aircraft meets the specified sensitivity requirements.
Performance Link Calculation To assess the performance of a link, we need to calculate the values of the total Carrierto-Noise ratio (C/N).
Energy per bit to Noise density ratio (Eb/N.
, and Bit Error Rate (BER) using the following formulas .
ya )ycycuycycayco ycA ya )ycycy ycA ya )yccycuycycu ycA ya = .
cA) ycycuycycayco Oe ycIyca yaAycO ycAycu yaAycOOycAOyayaya ycIyca = .
ycIycuycoyco ycuyce yceycaycaycycuy.
yaAyaycI = 2 yceycyceyca.
ayca/ycAyc.
1/2 yccyaA : information rate .
: bandwidth (H.
: modulation index
FEC
: Forward Error Correction A AA Kompiyang Karmana Putra.
Muhammad Suryanegara Voice Communication simulation using Mathematical Programming Language Simulation of voice communication here involves simulating how communication between pilots and ATC or communication between pilots in different aircraft can take place using VHF communication via the AMS(R)S satellite.
Figure 3 shows the block diagram of a voice simulation using QPSK modulation and an AWGN channel.
In this research, the VHF communication channel of the AMS(R)S satellite is simulated using an AWGN channel, where the performance of the AWGN channel is referenced to the Eb/No calculations from the satellite link budget.
Block diagram of voice communication simulation is presented on Figure 3.
Figure 3.
Block Diagram of Voice Communication Simulation Results and Discussion The results and analysis can be broadly categorized into two main sections: satellite link budget calculations and voice communication simulation.
The result of satellite link budget calculation.
In the simulation of satellite link budget calculations, the positions of the aircraft and satellite are constantly changing, as illustrated in Figure 2.
The effective distance calculation between the aircraft and satellite is obtained using the trigonometric formulas of the sine and cosine laws, resulting in the values shown in Table 1.
Table 1.
Results of Effective Distance Calculation from Aircraft to AMS(R)S Satellite Par
Unit
EES
Value 66,08 23,92 65,60 19,40 64,19 15,81 62,01 12,99 59,21 55,94 52,34 48,48 44,45 40,27 35,99 31,62 27,20 22,73 18,22 13,69 91,34 45,70 0,00 10,79 9,06 7,66 6,51 5,55 4,73 4,01 3,38 2,80 2,27 1,78 1,31 0,87 0,43 0,00 A AA Kompiyang Karmana Putra.
Muhammad Suryanegara : altitude of AMS(R)S satellite : earth radius : aircraft altitude from ground surface : elevation angle, the angle between the aircraft and the horizon of AMS(R)S : nadir off-set angle of AMS(R)S satellite : central earth angle between the earth, aircraft, and AMS(R)S satellite : effective distance between the aircraft and AMS(R)S satellite .
lant rang.
From the calculations in Table 1 above, it can be observed that the changing positions of the aircraft and satellite result in varying distances, with the closest distance being 600 km and the farthest distance reaching 2,833 km Table 2 shows the results of the satellite uplink link budget calculation, which is the link budget from the aircraft to the satellite.
The transmission parameters in the aircraft are RF Power (PT.
= 16 watts, antenna gain (GT.
= -1 dBi, and assumed feeder losses (FLT.
= 2 dB.
Meanwhile, the receiving antenna gain on the satellite (GR.
is determined to be 8 dBi, and assumed feeder losses at the satellite (FLR.
= 1 dB.
The satellite uplink link budget calculation simulates the calculations performed in the Studies on WRC-23 agenda item 1.
, where the results are the Still, in this research, the author adds the parameter of changing the elevation angle every 5ycu and calculating C/Nup.
In the C/Nup calculation, the assumption of parameters is G/T = 1 and BW = .
MHz.
Table 2.
The Result of Satellite Uplink .
ircraft to AMS(R)S) Link Budget Calculation Par
Unit
MHz 137
VHF Transmitter on the Aircraft
PTx
PTx
dBW 12,04 12,04 12,04 12,04 GTx
FLTx
EIRP
dBW 9,04 9,04 9,04 9,04 Transmission Losses FSL
144,3 142,6 141 139,5
PFDe dBW/ -139 -137 -136 -134
VHF Receiver on the AMS(R)S Satellite GRx
FLTx
PRx
dBW -136 -135 -133 -131
PRx
dBm -106 -105 -103 -101
PRx_tar dBm -107 -107 -107 -107
Rxmar
[C/N] uplink
C/Nu 12,57 14,27 15,89 17,39 Value 12,04 12,04 12,04 12,04 12,04 12,04 12,04 12,04 12,04 12,04 12,04 12,04 12,04 12,04 12,04 9,04 9,04 9,04 9,04 9,04 9,04 9,04 9,04 9,04 9,04 9,04 8,04 6,04 4,04 2,04 138,1 136,9 135,9 -133 -132 -131
134,2 133,5 132,9 132,4
-129 -128 -128 -127
131,6 131,3 131,1 130,9 130,8 130,8
-126 -126 -127 -129 -131 -133
-0,8
-2,2
-3,9
-2,8
-5,5
-6,8
18,74 19,94 20,99 21,91 22,70 23,40 23,99 24,50 24,93 25,28 25,56 24,78 22,93 21,03 19,06
A AA Kompiyang Karmana Putra.
Muhammad Suryanegara
PTx
GTx
FLTx
EIRP
FSL
PFDeff GRx FLRx PRx PRx_tar Rxmar C/Nup : operating frequency : altitude of AMS(R)S satellite : elevation angle, the angle between the aircraft and the horizon of AMS(R)S : effective distance between the aircraft and AMS(R)S satellite .
lant rang.
: VHF transmitter power level RF on the aircraft : antenna gain on the aircraft : Feeder losses at transmitter .
: EIRP at aircraft : Free Space Losses : Scintillation Losses : Polarization Losses : Effective Power Flux Density : antenna gain at receiver (AMS(R)S) : Feeder losses at receiver (AMS(R)S) : received RF power level on the AMS(R)S : The target received RF power level on the AMS(R)S satellite : margin level on the receiver : Carrier to Noise Ratio uplink From the calculations in Table 2, it can be observed that the value of C/Nup ranges from 57 dB to 25.
56 dB.
The highest C/Nup value is obtained at a distance of 635 km or an elevation angle of 70ycu, between the aircraft and the satellite.
At this distance, the aircraft is closest to the satellite, and the antenna gain in that area has not yet decreased below -1 dBi.
Table 3 shows the results of the satellite downlink link budget calculation, which represents the link budget from the satellite to the aircraft.
The calculation of the satellite downlink link budget also simulates the calculations conducted in the Studies on WRC-23 agenda item 1.
The results are the same, but in this research, the author added parameters for the variation of elevation angle every 5ycu, and C/Ndown calculation.
In C/Ndown calculation assumes parameters of G/T = 1 and BW = .
MHz.
Based on the Studies on WRC-23 agenda item 1.
7, the link budget calculation reveals that the maximum power level required to cover the entire slant range from the aircraft to the satellite is greater than 300 Watts.
To optimize RF power efficiency in the satellite.
ICAO has decided that one AMS(R)S satellite should be designed to cover the aircraft-to-satellite elevation angle range of 20ycu to 70ycu herefore, the RF power required in the satellite is only 85 watts.
A AA Kompiyang Karmana Putra.
Muhammad Suryanegara Table 3.
The Result of Satellite Downlink .
ircraft to AMS(R)S) Link Budget Calculation Para Unit
MHz 137
VHF Transmitter on the AMS(R)S Satellite PTx
PTx dBW 19,29 19,29 19,29 19,29 19,29 GTx
FLTx
EIRP dBW 26,29 26,29 26,29 26,29 26,29 Transmission Losses FSL
144,3 142,6 141 139,5 138,1
PFDeff dBW/ 121,7 120,0 118,4 116,9 115,6 PFDrec dBW/ 116,2 116,2 116,2 116,2 116,2 PFDm dBW/ -5,5 -3,8 -2,2 -0,7 VHF Receiver on the Aircraft
GRx
FLTx
PRx dBW -129 -127 -126 -124 -123
PRx
dBm -99,0 -97,3 -95,7 -94,2 -92,8 Value 19,29 19,29 19,29 19,29 19,29 19,29 19,29 19,29 19,29 19,29 19,29 19,29 19,29 19,29 -0,8 -2,2 -3,9 -5,5 26,19 26,09 25,64 25,19 24,49 23,79 22,84 21,89 20,44 18,99 17,54 16,09 14,44 12,79 136,9 135,9 135 134,2 133,5 132,9 132,4 132 131,6 131,3 131,1 130,9 130,8 130,8 114,4 113,3 112,4 112,6 111,9 112,3 112,8 113,4 115,0 115,8 117,5 118,4 120,3 122,3 116,2 116,2 116,2 116,2 116,2 116,2 116,2 116,2 116,2 116,2 116,2 116,2 116,2 116,2 -1,3 -2,2 -4,1 -6,1 -122 -121 -120 -120 -119 -120 -120 -121 -122 -123 -126 -129
-91,6 -90,6 -89,7 -89,9 -89,2 -89,6 -90,1 -90,6 -92,3 -93,0 -95,8 -98,6
-133 -137
102,5 106,5
[C/N] downlink
C/Ndow dB
28,83 30,52 32,15 33,64 34,99 36,19 37,24 38,16 37,96 38,65 38,25 37,75 37,18 35,53 34,82 33,03 32,19 30,28 28,31
: operating frequency : elevation angle, the angle between the aircraft and the horizon of AMS(R)S : effective distance between the aircraft and AMS(R)S satellite .
lant rang.
PTx : VHF transmitter power level RF on the AMS(R)S satellite GTx : antenna gain on the AMS(R)S satellite FLTx : Feeder losses at transmitter (AMS(R)S satellit.
EIRP : EIRP at AMS(R)S satellite FSL : Free Space Losses : Scintillation Losses : Polarization Losses PFDeff : Power Flux Density at receiver .
PFDrec : Power Flux Density recommendation by ICAO at receiver .
PFDm : margin of Power Flux Density at receiver .
GRx : antenna gain on the receiver .
FLRx : Feeder Loss on the receiver .
altitude of AMS(R)S satellite A AA Kompiyang Karmana Putra.
Muhammad Suryanegara PRx : received RF power level on the receiver .
C/Ndown : Carrier to Noise Ratio downlink If one AMS(R)S satellite only serves coverage as calculated above, a minimum satellite constellation of 40 satellites is required to cover the entire Earth's surface.
This can be seen from Table 1, where the aircraft-to-satellite elevation angle from 20ycu to 70ycu covers only 9ycu .
,79ycu to 1,78ycu ) of the earth's central angle.
If the entire Earth's surface is calculated as 360ycu the minimum number of satellites needed is 360ycu yccycnycycnyccyceycc ycayc 9ycu , resulting in 40 satellites.
If the uplink and downlink link budget calculations are simulated as end-to-end communication .
ircraft-satellite-aircraf.
, the values of C/Ntotal.
Eb/No, and BER can be calculated as shown in Table 4.
The aircraft-to-satellite elevation angle ranges from 20ycu to 70ycu assuming the use of QPSK modulation.
FEC = A and ROF = 20%.
Results of the link budget calculation for AMS(R)S-VHF satellite is presented on Table 4.
Table 4.
Results of the Link Budget Calculation for AMS(R)S-VHF Satellite (End-to-End Communicatio.
Parameter Unit Value .
[C/N]up 18,74 19,94 20,99 21,91 22,70 23,40 23,99 24,50 24,93 25,28 25,56 [C/N]down 34,99 36,19 37,24 38,16 37,96 38,65 38,25 37,75 37,18 35,53 34,82 [C/N]tot 12,20 12,86 13,42 13,92 14,21 14,57 14,74 14,86 14,92 14,77 14,74 Eb/No BER
BER
From the calculations above, it can be observed that as the distance between the aircraft and the satellite decreases within the range of aircraft-to-satellite elevation angles from 20ycu to 70ycu , the values of C/N.
Eb/No, and BER improve.
Figure 4 shows the graph of C/Ntotal and Eb/No for the end-to-end communication simulation .
ircraft-satellite-aircraf.
the effective distance from the aircraft to the AMS(R)S satellite .
lant rang.
Figure 4 depicts the BER vs.
Eb/No graph for QPSK modulation.
Figure 4.
Graph of Eb/No and C/N vs Slant Range aircraft to AMS(R)S .
Graph of BER vs.
Eb/No for QPSK modulation A AA Kompiyang Karmana Putra.
Muhammad Suryanegara 2 Result and analysis of voice Communication Simulation using Mathematical Programming Language.
The Voice Communication simulation, following the block diagram in Figure 3, illustrates the pilot communicating with the ATC or with other pilots in different aircraft.
Therefore, the VHF satellite communication link is simulated using an AWGN channel with an Eb/No value of 10 dB, referring to the link budget calculation that sets the maximum Eb/No value at 14 dB.
In the voice communication simulation using Mathematical programming language, the audio is recorded in the 'wav' file format and processed according to the standard Pulse Code Modulation (PCM) technique.
The process involves down-sampling, quantization, and The audio signal is then modulated using QPSK and transmitted through an AWGN channel with a frequency of 137 MHz and an Eb/No of 10 dB.
On the receiver side, the process is the reverse of the transmission side, involving demodulation, decoding, re-sampling, filtering, and file reconstruction.
The results of the voice communication simulation are shown in Figure Figure 5.
The results of the Voice Communication Simulation Using Mathematical Programming Language From Figure 5, it can be observed that the simulation results of the voice communication show that the original audio signal closely matches the received signal both before and after filtering, both in the time domain and frequency domain.
When listened to directly, the quality A AA Kompiyang Karmana Putra.
Muhammad Suryanegara of the received audio is still apparent.
However, the quality is slightly decreased compared to the original audio .
ated at 4 out of a standard range of 1-.
Here is the graph of BER vs.
Eb/No for QPSK modulation, both theoretically and based on simulation results using an AWGN channel, as shown in Figure 6.
Figure 6.
BER vs.
Eb/No for QPSK Modulation The higher the value of Eb/No in a communication link, the better the network performance, as indicated by a smaller BER value.
The satellite link budget calculation conducted in this research is a re-simulation of the link budget calculation performed by ICAO, with more detailed parameters regarding the changes in the aircraft's elevation angle concerning the satellite.
While the ICAO calculation considers changes in elevation angle of 10ycu , this article incorporates calculations for changes in elevation angle every 5ycu .
The author also included performance calculations such as C/N.
Eb/No, and BER as references for conducting voice communication simulations, particularly the Eb/No values used in evaluating the performance of the AWGN channel.
The feeder link for communication from the AMS(R)S satellite to the ground segment has not been discussed in this research by the ICAO study.
If the FSS for the feeder link is determined, it would be possible to calculate the end-to-end link budget from the aircraft satellite ground and simulate voice communication between the pilot and ATC, and vice versa.
A AA Kompiyang Karmana Putra.
Muhammad Suryanegara Conclusion This research has analyzed the satellite link budget calculations using parameters according to the study conducted by ICAO.
The parameters used include a satellite altitude of 600 km, with a service coverage angle of 20A to 70A from the aircraft to the satellite.
The satellite's RF power is 85 watts, with a satellite antenna gain of 8 dBi.
The aircraft's RF power is 16 watts, with an aircraft antenna gain of -1 dBi.
The aircraft's recommended minimum received power flux density (PFD) is -116.
2 dBW/mA, corresponding to a minimum receiver sensitivity of -107 dBm and a maximum C/Nup value of 25.
56 dB.
The minimum receiver sensitivity at the aircraft is -93 dBm, with a maximum C/Ndown value of 38.
65 dB.
Furthermore, the simulation of the endto-end link budget calculation .
ircraft-satellite-aircraf.
showed variable results based on the changing distance between the aircraft and the satellite.
The C/Ntotal ranged from 12.
20 to 14.
dB, the Eb/No ranged from 11.
2 to 14 dB, and the BER ranged from 3x10-7 to 5x10-12.
References