ku kaband experiment report 2006

Joko SuryanaSchool of Electrical Engineering and Informatics ITB

Experimental Laboratory for WINDS/Ka-band Experiments

Joko SuryanaSchool of Electrical Engineering and Informatics

Institut Teknologi Bandung, INDONESIA


Presentation Summary

• Our Past Ku-band SatCom Application Experiments ( 2002-2006 )

• Our Next Ka-band SatCom Experimental Laboratory ( 2007-2009 )

• Appendix : Precipitation, Rain Attenuation and Tropospheric Scintillation in Indonesia as Big Challenge for Evaluate the WINDS performance


Our Past Japanese Ku-band Satellite Application Experiments in ITB, Indonesia ( 2002-2006)


Outline• EXPERIMENT#1 : STUDY OF INTEGRATING KU-BAND

SATELLITE NETWORK WITH TERRESTRIAL GSM CELLULAR NETWORK FOR IMPLEMENTING THE ENHANCED LOCATION-BASED SERVICES ( ITB, INDONESIA & USM MALAYSIA )

• EXPERIMENT#2 : AUTOMATIC SATELLITE TRACKING DISH ANTENNA SYSTEM FOR BROADBAND IP-BASED AMBULANCE TELEMEDICINE USING SATELLITE ( ITB, INDONESIA & TOKAI UNIV JAPAN )

• EXPERIMENT#3 : STUDY OF SECURED IP-BASED VIDEOCONFERENCE OVER KU-BAND SATELLITE LINK BETWEEN BANDUNG-TOKYO ( ITB INDONESIA & NICT JAPAN )


EXPERIMENT#1 : Hybrid Satellite and Celluler Networking for Enhanced LBS

Experiment Setup


LBS Experiment Preparation


LBS Experiment• The LBS experiment has the objective to extend

the multi-media communication capability of Experimental Satellite IP network by connecting it to a cellular communication system.

• By its capability, this system can be considered as a platform of a LBS (location based services); in this case we can find its application in : – traffic monitoring– simple news gathering– and with several modifications can be developed as a

natural disaster monitoring system.


LBS Experiment• The experiment consists of the

development of distant control system where a remotely located camera will be controlled by a faraway monitoring station via both cellular communication system and satellite communication system.

• The video clips captured by the remote camera then can be downloaded by the monitoring station.


LBS Experiment

• The experiment setup consists of three different systems : – Cellular system with two communicating GSM

cell phones with LBS Algorithm Software– LAN computers with Software for Remote

LBS– Satellite communication systems ( JCSAT 1B)


LBS Experiment• A video camera or cellular phone camera as mobile part in

location C (moving) takes pictures or short video clips, then send them as MMS messages or streams via the cellular system so they can be received by another cellular phone in location B.

• By a program in a LAN host in location B ( fixed part ), the MMS message or streams will be transferred from the cellular phone via data cable to host computer in location B.

• Subsequently, the message will be transmitted to a computer located in A. The remote camera itself will be remotely controlled by the monitoring station in location A.

• Using this method, pictures or short video clips are transferred as the cellphone moves within the cellular coverage. This experiment is conducted together with another university (e.g. Universiti Sains Malaysia)


LBS Experiment

Prototype of Serial camera and Stream Controller to GSM Modem for Mobile Part developed by ITB

Nokia Module for Machine to Machine Communication for Mobile Part (non Realtime Applications)

Desktop at LTRGM equipped Specialized Software and networked with Siemens GSM Handset as Fixed

Part of LBS Experiment


Emergency assintance at ITB campus


EXPERIMENT#2 : GEO satellite-based Emergency Telemedicine

• This research is addressed to report our evaluation study of GEO satellite-based Emergency Telemedicine services which installed in an ambulance car.

• From the measurement results , we concluded that the satellite is almost visible in Bandung, so the shadowing due to high building in Bandung is not degrading the transmission of vital biosignals from Ambulance to Hospital.


Vital Biosignals• The provision of effective emergency

telemedicine is the major field of interest discussed in this study.

• Ambulances is a common example of possible emergency sites, while critical care telemetry and telemedicine follow-ups are important issues of telemonitoring.

• The emergency telemedicine allows the transmission of vital biosignals such as ECG monitor, Airway, Abdomen Echo, and Light Reflex


Vital Biosignals


GEO-stationary-basedEmergency Telemedicine

• Some case studies have suggested that data transmission via geostationary satellites offer great potential for emergency medical communications.

• Conversely, the shadowing (blocking) effects of many buildings and trees lining city streets will pose a problem for communication with satellites.


GEO-stationary-basedEmergency Telemedicine

• In this research , we describes a newly-developed high-precision Ku-band GEO satellite tracking system for Emergency Telemedicine on the Ambulance.

• The core of this tracking system comprises a quadrant detector for estimating the absolute coordinate of the satellite, while its relative coordinates are estimated by a GPS-based continuous kinematic positioning system.

Super Ambulance Car

Automatic Tracking Dish


Super Ambulance ( Tokai Univ )


Target satellites• A geostationary satellite (GEO) may be used in areas

near the equator and flat areas with few obstructions. Palapa C2 satellite is one of Indonesia satellites which has very high elevation angle ( 75-85 degree ) and good Ku-band coverage over 60% of Indonesia archipelago as illustrated in figure 4 below.

• On the other hand, right now under NiCT-Japan project on WINDS applications in Indonesia, we also have opportunity for using Gigatbit Ka-band Japanese Satellite, WINDS in Indonesia which has elevation angle 48 degree over West Java area.

• These two satellite are our target satellite for GEO-stationary based Emergency Telemedicine.


Target satellites :Palapa C2 and WINDS


System Designa.Tracking mechanics• We have mounted on the roof of an ambulance

two tracking systems that can operate in the 25-90 degree angle of elevation range and up to a continuous 360-degree azimuth range to track a Ku/Ka-band geostationary satellite .

• The drive system features a compact, simple design, and mechanically controls a Cassegrain antenna 50 cm in diameter (weight: kg; target radio bands: Ku and Ka; feeder unit: optional).


System Designb. GPS interference positioning (Continuous

kinematic positioning)• GPS interference positioning and continuous

kinematic positioning are technologies used to receive signals simultaneously sent from GPS satellites at two sites, and to determine the relative coordinates of one receiving point against the other based on the measured phase of the carrier wave.

• We obtain directional data in 3D coordinates from three GPS receivers.


System Designc. Quadrant detector• Data transmission from an ambulance to the satellite is

the major part of data flow in the current system. • However, with transmission four spatially separated

receiving circuits (all located the same distance from the center of the Cassegrain antenna feeding unit) concurrently catch weak pilot beacons sent from the satellite.

• Four DSPs along the time axis integrate these received signals to calculate four magnitudes of electric power. The differences between these four values of arriving power are determined based on the beacon angle and four spatial coordinates.


System Design

d. Accelerometer and inclinometer• We used commercially available

accelerometers and inclinometers to determine the conditions of emergency ambulances in operation.


System Design


Tracking Protocola. Initial acquisition• The first method used to locate a satellite. The satellite’s six

elements, time, present location (GPS data), and antenna elevation are easily calculated. Optimal positions are sequentially calculated according to bearings (using a laser-gyro at present).

b. Tracking• Comparing and controlling signal strength from a satellite using QD.c. Re-acquisition• When a vehicle changes direction at a traffic intersection or brakes or

accelerates, it frequently needs to reacquire the signal, since inertia tends to force the antenna into a position precisely opposite anoptimal position.

d. Distinguishing a traffic intersection from shadowing• A traffic intersection can be distinguished from shadowing using GPS

data.


Tracking Protocol


Propagation Measurement Results using Satellite Visibility Concept

• For evaluating the transmission quality due to the shadowing, we have performed the satellite visibility measurements at Bandung, Indonesia .

• From the measurement results , we concluded that the satellite is almost visible in Bandung, so the shadowing due to high building in Bandung is not degrading the transmission of vital biosignals from Ambulance to Hospital.


Propagation Measurement Path in Bandung

Super Ambulance Car



Propagation Measurement Results


EXPERIMENT#3 : Videoconference Security over Ku-band Satellite Link

• Security and privacy are among the most critical problems of videoconference over IP-based network. . For achieving large number of video conferencing users over the IP-based network, it is mandatory to provide secure authentication and authorization mechanisms with the applications.

• Two main security mechanisms used are authentication and data encryption . – Data authentication is used to ensure that the doctors sending the

messages are who they claim to be. It is also used to make sure that message information was not modified during the transit .

– Data encryption, which protects the confidentiality of the communication, is used to ensure that only the intended person can decrypt and read a message . In order to provide authentication service both the servers and the clients involved in the call process have to support these security mechanisms.


Secure Videoconference Demonstration at CRL


Secure Videoconference Equipments ( Ken Umeno Lab, CRL )


Chaotic Video Encryption : Encryptor( by Dr.Ken Umeno )


Chaotic Video Encryption : Dencryptor( by Dr.Ken Umeno )


Experimental Scenarios of Secured Ku-band ITB-CRL Videoconferencing


Last Experiment• Our last experiment on secured videoconference had

done at October, 27 2003 which connected CRL and ITB using Ku-band Japanese Satellite JCSAT-1B.


Our Next of Japanese Ka-band Satellite Application

Experiments in ITB, Indonesia using WINDS ( 2007-2009 )


Outline

• Research Topics• Experiment Facilities• Experiment Packages• First Year Experiment• Research Summary


Research Topics ( 3 years )Antenna and Propagation• Characterization of Atmospheric Gases, Cloud

and Hydrometeor Attenuation at Ka-band • Depolarization, Scintillation and BW Coherence

Measurements at Ka-band• Short-Baseline Site Diversity for Mitigating the

Ka-Band Rain Attenuation • Antenna System for Mobile Satellite

Communication using GEO Ka-band Satellite


Research Topics ( 3 years )Physical Layer Ka-band Satellite Link• Software-define Radio Concept for Adaptive

Modulation and Coding on Ka-band Satcom • Adaptive Power and Rate Control for Satellite

Communications in Ka Band • Ka-band Fade Detection and Compensation

Techniques • Performance of UWB signals transmission over

Ka-band Satellite Channel


Research Topics ( 3 years )Higher Layer Application• Secured and Reliable Video Communication over Ka-

band Satellite System • Inter University Grid Computing System using Ka-

band Satellite Link Infrastructure• Low cost Portable Ka-band Terminal for Emergency

Services After Disaster• Performance Evaluation of TCP/IP over ATM Satellite

Ka-band Links• Performance Evaluation of HAPS-WINDS Networking

for Gap Filler Applications


Existing Facilities ( Ku band )• Earth Station :

– Operating Frequency : Ku-band – Type : NEXTAR, 2 Mbps– Interface : Videoconference, TCP/IP

• Beacon Receiver :– Operating Frequency : Ku-band

• Meteorological Sensors :– Raingauge, Temp, Humi, Solar Activities, Wind, Bar

• BER Meter • Spectrum Analyzer : 0 – 8 GHz• Network Analyzer : 0 – 13 GHz• Internet :

– 2 Mbps Ku-band, 40 Mbps FO, 100 Mbps Ethernet


Existing Facilities ( Ku band )


Expected Facilities• Fixed Ka-band Earth Station• Portable Ka-band Earth Station• Ka-band Beacon Receiver• Ground-based Radar• Raingauge Network• SDH / ATM Analyzer• Spectrum Analyzer : 0 – 35 GHz• Network Analyzer : 0 – 35 GHz• Terrestrial Interfacing : 3G / WiMAX / FO


Developed Facilities by ITB

• UWB ( Ultrawideband ) Sensor and Communication System

• SDR ( Software Defined Radio ) for Adaptive Modulation, Coding, Rate and Power Control of Ka-band Link

• Automatic Tracking Antenna System : Dish or Radial Slot Line

• WiFi / WiMAX / 3G Network Interfacing• Grid Computing System


Developed Facilities by Partner• Secure Video Transmission by Dr.Ken Umeno, NiCT

Japan ( existing partner )• Share Grid Computing Facilities by other Asian

Univiersities : Univ of Tokyo, KMITL Thailand, AdMU Philiphina, NTU Singapore ( expected partners )

• Telemedicine Facilities by Tokai Univ Hospital Japan and Hasan Sadikin Hospital Indonesia ( existing partners )

• Telelearning Facilities, NIME Japan ( existing partner )• Advanced DSP Facilities by University of Tokyo and

Electromagnetics Computing Facilities by Chiba University ( expected partners )

• HAPS by Waseda University Japan ( expected partner )


WINDS/Ka-band ExperimentsAntenna and Propagation

Physical Layer

Higher Layer


Ka-band Propagation Experiments

• Attenuation by Atmospheric Gases :– Oxygen– Water Vapor

• Hydrometeor Attenuation :– Rain – Cloud – Fog

• Depolarization– Rain– Multipath

• Other Factors– Scintillation– Bandwidth Coherence

• Mitigation Scheme– HAPS / WINDS


Ka-band Antenna Experiments

• Automatic Satellite Tracking Antennas– Self pointing– Fast Deployment– Emergency– Mobile

• Antenna Types :– Non Metalic Dish – Radial Slotline– Microstrip Phased Array

• Mitigation– Site Diversity


Physical Layer Experiments• Transmission Techniques :

– Adaptive Modulation, Code, Datarate and Power– Ultrawideband, Multiband OFDM

• Implementation Issues:– Software Defined Radios– Adaptive Rainfade Compensation– ATM over Ka-band in Tropical Area


Higher Layer Experiments• Applications :

– Field and Mobile Telemedicine– Multicast Telelearning– Grid Computing– Time and Location-based

Services

• QoS :– BER, Delay Throughput, Cell

Loss– Videoconference over ATM

• Security :– TCP/IP Layer– Application Layer


First Year Experiments : #1• Name of Experiment :

– Performance of WINDS at High Intense Rain• Configuration

– Loopback Test : Bandung-WINDS– Equipment : Ka-band Beacon Receiver, Raingauge, BER meter,

ATM Analyzer• Experiment Plan

– Required data rate (Uplink/Downlink : 1 -100) – Place to carry out the experiment : Bandung– Network configuration (point-to-point) – Time and period of the experiment : 2 month ( 2 days / week )– Dish Antenna 1.2 m

• Internet : available



– Performance of WINDS at High Intense Rain



– Short Baseline Site Diversity for WINDS• Configuration

– One ODU at Tokyo and two ODUs at Bandung– Equipment : IDU, Ka-band Beacon Receiver, Raingauge network,

Terrestrial WiFi Link• Experiment Plan

– Required data rate (Uplink/Downlink : 10 Mbps ) – Place to carry out the experiment : Tokyo-Bandung– Network configuration (point-to-point) – Time and period of the experiment : 4 month ( 2 days / month )– Fixed and Portable Dish Antenna 1.2 m




– Short Baseline Site Diversity for WINDS



– Secured Multicast Videoconference using WINDS• Configuration

– Multicast ( mesh or star )– Equipment : Chaotic Secure System, Videoconference system

• Experiment Plan – Required data rate (Uplink/Downlink : 2-4 Mbps ) – Place to carry out the experiment : NiCT-Bandung-NIME– Network configuration (mesh or star) – Time and period of the experiment : 3 month ( 1 day / month )– Fixed Dish Antenna 1.2 m




– Secured Multicast Videoconference using WINDS



– WINDS Visibility Study for Mobile Telemedicine Services• Configuration

– Point to point– Equipment : Portable ODU, Automatic Tracking Dish

• Experiment Plan – Required data rate (Uplink/Downlink : 2-4 Mbps ) – Place to carry out the experiment : NiCT-Bandung– Network configuration (point to point) – Time and period of the experiment : 3 month ( 2 days / week)– Portable Dish Antenna 1.2 m




– WINDS Visibility Study for Mobile Telemedicine Services

Super Ambulance Car



Research Summary


Member of Rainmen Association ( Thanks to Prof.Ong, Iida-san and Prof.Syed )


Member of Secured Men Association ( Thanks to NiCT )


Help to Beatiful Medical Nurses ( Thanks to Tokai University )


Appendix : Rainfall, Rain Attenuation and Tropospheric Scintillation Characteristics in INDONESIA


Ku-band Propagation Measurement System at ITB Bandung

• The Ku-band propagation measurement system uses a small antenna and a front end shared by the beacon receiver and the Earth Station IDU as shown in figure below



• The PC-based data acquisition system consists of eight channels for measuring the seven meteorological parameters of six sensors and one propagation parameter, i.e beacon level.

• The PC hardware and software for data collection receives all data transmitted from data acquisition board, logs the data to disk, and displays the collected data for user viewing which implemented with LabView.


Rainfall Rate Measurement Results• Rainfall Rate data is needed for determining the degree of rain

attenuation in the Ku-band satellite communication system. • Field measurements and recordings for long time periods are the

best (empirical) method to know the rainfall rate in a country.• The two years of our experiment results indicate that the measured

R0.01 rainfall rate at Bandung is 120 mm/h. • The P region of ITU-R model is over estimate for Bandung, so we

suggest that Q-region of ITU-R model is more suitable for Bandung.• Other tropical Indonesian cities confirmed with our conclusion that

some cities in Indonesia have not only P-region of ITU-R model (such as Padang, Bengkulu an Makassar), but also N (such as Jayapura) and Q-region ( such as Surabaya )


Rainfall Rate Measurement Results


Rainfall Rate Measurement Results

• The table 1 shows us about the rainfall rate profile of 24 tropical cities in Indonesia


Measured vs Predicted Rainfall Ratefor Indonesian Cities

• Prediction methods is another way to determine the rainfall rate but with some limitations. The rainfall rate prediction such as the ITU-R Rep. 563-4 and the Global Crane model can be used to do this.

• Some experts consider these models are not accurate enough, because there were too few samples used when developing the models.

• The comparison of measured and predicted value of rainfall rate at Bandung [6]


Measured vs Predicted Rainfall Ratefor Indonesian Cities

• The comparison of measured and predicted value of rainfall rate at Padang [4] and Surabaya [1]


New Model of Rainfall Rate for Indonesian Cities

• The rainfall rate prediction model which applicable especially for Indonesia, can be developed more accurate and convincingly with the availability of field measurements as presented above.

• By using the data, and added to it (other) data concerning rain and thunderstorm days from the Indonesian Meteorological and Geophysical Institute, the Rainfall Rate Prediction Model for the Indonesia archipelago becomes [7]:R0.01 = f ( Lat,Long,M,Mm )

= 128.192 – 0.037Lat – 0.393Long + 0.012M + 0.017Mm with : R0.01 = rainfall-rate 0.01 percent of time in a year (mm/h)

M = average rainfall a year (mm)Mm = maximum rainfall (monthly) in 30 yearsLat = latitude and Long = longitude


New Model of Rainfall Rate for Indonesian Cities

• The following table shows us the comparisons of measured and new model of rainfall rate for Indonesian cities using the above equation.

City R0.01 R0.01 ErrorMeasured New Model

Bandung 120 118.4 1.33%Cibinong 159 155.8 2.02%Denpasar 109 109.5 0.50%Jatiluhur 109.2 113 3.45%Maros 148 146.1 1.29%Padang 146 153.7 5.27%Putussibau 152 144.7 4.82%Surabaya 119.6 116.1 2.95%Tanahmerah 138 142.2 3.02%

Mean Error 2.58%RMS Error 3.00%


Ku-band Rain Attenuation Measurement Results

• The International Telecommunication Union, ITU, has categorized Indonesia as Region P, a country with very high rain precipitation.

• According to ITU’s version, rain intensity that will cause the interruption of a communication link for 0.01% per year is 145 mm/hour. Such rain intensity can cause 28 db rain attenuation for a link working in the 14 GHz band; that is pretty high.

• The rain attenuation for satellite links can be calculated usingfollowing models: ITU – R, SAM, Global Crane and DAH. And to confirm which is the prefered model to be used in Indonesia, field measurements should also be carried out.

• The two years of our experiment results indicate that the measured A0.01 rain attenuation is 17 dB [6]. It also has been found out, after analysis, that the DAH Model for rain attenuation prediction is valid for Indonesia, besides the ITU Model.


Ku-band Rain Attenuation Measurement Result at Bandung


Ku-band Rain Attenuation Measurement Result at Padang


Ku-band Rain Attenuation Measurement Result at Cibinong


Wetting Antenna as correction factor• The two years of our experiment results indicate that the

measured A0.01 rain attenuation is 17 dB, this value is about 3 dB greater than computed A0.01 using Q-region of ITU-R model. This suggests that there could be another significant attenuation mechanism present.

• The effects of water on the antenna radome and reflector wettingare the possible cause of the higher attenuation measured .

• So, we also have performed experimentally the magnitude of the signal loss when the antenna reflector and the antenna feed hornradome surfaces are wet and its correlation to rain rates which is simulated by using the water sprayer during clear sky condition

• The wetting antenna test results introduced about 2.5 dB losses at 40 mm/h simulated rain rate which is close with our simple theoretical approach ( 2.7 dB )


Wetting Antenna as correction factor


Rainfall Rate and Rain Attenuation Statistics at Bandung, Indonesia

• From the experiment results [1], we have found out that on rainfall rate R0.01 120 mm/h, the rain attenuation A0.01 measured is around 17 dB.


Rainfall Rate and Rain Attenuation Statistics at Bandung, Indonesia

• Relating to the Rainfall and Rain Attenuation Characteristic in the 'regular' rainy (October-April) and 'regular' nonrainy ( April-October) seasons, we noted that the higher rain intensity occurred at May, June, October and November. And we also see on the corresponding maximum rain attenuation recorded per month that there is a high rain attenuation (33 dB ) in October.


ITU-R Model for Ku-band Tropospheric Scintillation at Bandung

• Tropospheric scintillation is a rapid fluctuation of signal amplitude and phase due to turbulent irregularities in temperature, humidity and pressure, which translate into small-scale variations in refractive index.

• Scintillation becomes important for low margin systems operating at high frequency and low elevation angles. When receiving a Ku-band (or above) signal at low elevation angles (<15 degrees).



• For calculating the tropospheric scintillation using ITU-R model, the required Input Parameter are [3]: Antenna diameter , Operating Frequency and Elevation Angle.

• Step 1 : Determine L, the slant path distance to the horizontalthin turbulent layer, from :

• Step 2 : Determine the Z from :

• Step 3 : Determine the antenna averaging factor G(z) from :

• Step 4 : The r.m.s amplitude scintillation, expressed as dx , the standard deviation of the log of the received power, is then

• given by :

62 10]sin5.8sin25.72017.0[ xL θθ −+=

fL

DZ 685.0=

⎪⎩

⎪⎨

⎧

><<−

<<−=

1,1.00.15.0,4.05.0

5.00,4.10.1)(

zzz

zzzG

2/185.012/7 )]([][csc025.0 zGfx θδ =



• Using the ITU-R Scintillation Model, we can calculate the rms amplitude scintillation for Bandung as Table 1 below :


Ku-band Tropospheric Scintillation Data Processing for Bandung

• In the pre-processing step, we were collecting clear air condition data (10 minutes/day) from two years propagation data . The collected clear air data sets consist of rainy season and dry season sets for representing the marked seasonal dependence.

• The simpler software technique for smoothing signals consisting of equidistant points is the moving average. An array of raw data [y1, y2, …, yN] can be converted to a new array of smoothed data.



• For calculating the long term scintillation PDF, we extract the scintillation data using special LPF, namely Savitzky-Golay Filter [4] from the six months data sets.

• A much better procedure than simply averaging points is to perform a least squares fit of a small set of consecutive data points to a polynomial and take the calculated central point of the fitted polynomial curve as the new smoothed data point. The smoothed data point (yk)s by the Savitzky-Golay algorithm is given by the following equation:



• From the data processing results [7], we find out that the scintillation in tropical region is seasonal dependence, reaching variance 0.4 dB (maximum) in rainy season and 0.2 dB (minimum) in dry season.

• This results are depicted as in figure below :



• We also noted that the long term PDF and its spectrum shape using Savitzsky-Golay LPF is very closely with the conventional moving average LPF as illustrated in figures :


Summary• The two years of our experiment results indicate that

the measured R0.01 rainfall rate at Bandung is 120 mm/h. Therefore, the P region of ITU-R model is over estimate for Bandung, so we suggest that Q-region of ITU-R model is more suitable for Bandung.

• Another previous measurements which had performed in other tropical Indonesian cities confirmed with our conclusion that some cities in Indonesia have not only P-region of ITU-R model (such as Padang, Bengkulu an Makassar), but also N (such as Jayapura) and Q-region ( such as Surabaya ).


Summary• From the comparisons of predicted rainfall rate well

known models with measured rainfall rate of tropical cities in Indonesia, we can see that there are significant differences. So the new model of rainfall rate should be developed which has small deviation. It also has been found out, after analysis, that the DAH Model for rain attenuation prediction is valid for Indonesia, besides the ITU Model.

• The wetting antenna test results introduced about 2.5 dB losses at 40 mm/h simulated rain rate which is close with our simple theoretical approach ( 2.7 dB ). So we can make the correction of the measured rain attenuation at Bandung by using wetting antenna factor


Summary• Relating to the Rainfall and Rain Attenuation

Characteristic in the 'regular' rainy (October-April) and 'regular' nonrainy ( April-October) seasons, we also noted that the higher rain intensity occurred at may, June, October and November. We also see that on october, there is a short duration high rain attenuation (33 dB).

• On the other hand, during these two years Ku-band propagation measurement, we also find out that the tropospheric scintillation in tropical region is seasonal dependence, reaching variance 0.4 dB (maximum) in rainy season and 0.2 dB (minimum) in dry season.

ku kaband experiment report 2006

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