This document discusses potential interference between transmissions in the 3550-3700 MHz band and reception by C-band earth stations in the 3700-4200 MHz band. It notes that out-of-band emissions from transmitters in 3550-3700 MHz could interfere with receivers in the adjacent 3700-4200 MHz band. To prevent this, coordination and exclusion zones may be needed to separate transmitters and receivers by sufficient distance. The document calculates the required path loss and separation distance based on transmitter power and receiver interference specifications.
DEVELOPMENT OF A SOFTWARE TOOL FOR PLANNING MICROWAVE SYSTEMS AT ABOVE 10 GHz, ESTIMATING CO-CHANNEL INTERFERENCE AND RAIN ATTENUAITON, USING ITU-MODEL ON MATLAB AND TO VALIDATE THE SOFTWARE AGAINST AN INDUSTRY STANDARD (CONNECT) TOOL”
This presentation deals with topics such as Electromagnetic Spectrum, Wireless Propagation, Signals, Signal propagation effects, Spread spectrum and cellular systems.
DEVELOPMENT OF A SOFTWARE TOOL FOR PLANNING MICROWAVE SYSTEMS AT ABOVE 10 GHz, ESTIMATING CO-CHANNEL INTERFERENCE AND RAIN ATTENUAITON, USING ITU-MODEL ON MATLAB AND TO VALIDATE THE SOFTWARE AGAINST AN INDUSTRY STANDARD (CONNECT) TOOL”
This presentation deals with topics such as Electromagnetic Spectrum, Wireless Propagation, Signals, Signal propagation effects, Spread spectrum and cellular systems.
ULTRA WIDE BAND TECHNOLOGY
BODY AREA NETWORKS
BW ³ 500 MHz regardless of fractional BW
UWB is a form of extremely wide spread spectrum where RF energy is spread over gigahertz of spectrum
Wider than any narrowband system by orders of magnitude
Power seen by a narrowband system is a fraction of the total UWB power
UWB signals can be designed to look like imperceptible random noise to conventional radios
AM – Frequency spectrum – vector representation – power relations – generation of AM – DSB, DSB/SC, SSB, VSB AM Transmitter & Receiver; FM and PM – frequency spectrum – power relations : NBFM & WBFM, Generation of FM and DM, Armstrong method & Reactance modulations : FM & PM frequency.
Takeoff Projects helps students complete their academic projects.You can enrol with friends and receive modulation techniques kits at your doorstep. You can learn from experts, build latest projects, showcase your project to the world and grab the best jobs. Get started today!
https://takeoffprojects.com/modulation-techniques
Modulation schemes used in wireless technologiesVijitaaDas
As we all know, in today's world, Wireless Technology is one of the most important method of communication between one device and other devices. This communication system uses a very clever technique called Modulation Technique or schemes to increase the reach of the signals. Another reason is to allow the use of smaller antenna. This PPT is mainly focused on the modulation schemes that helps in the communication process of Bluetooth, Zigbee, Wi-Fi and UWB.
A communication system is for transmitting and receiving the information that users want to exchange. To make up a communication system, we can adopt the FDMA, TDMA, CDMA, and so on. In this presentation, we introduce a simplified communication blocks with which we can understand a modern system.
ULTRA WIDE BAND TECHNOLOGY
BODY AREA NETWORKS
BW ³ 500 MHz regardless of fractional BW
UWB is a form of extremely wide spread spectrum where RF energy is spread over gigahertz of spectrum
Wider than any narrowband system by orders of magnitude
Power seen by a narrowband system is a fraction of the total UWB power
UWB signals can be designed to look like imperceptible random noise to conventional radios
AM – Frequency spectrum – vector representation – power relations – generation of AM – DSB, DSB/SC, SSB, VSB AM Transmitter & Receiver; FM and PM – frequency spectrum – power relations : NBFM & WBFM, Generation of FM and DM, Armstrong method & Reactance modulations : FM & PM frequency.
Takeoff Projects helps students complete their academic projects.You can enrol with friends and receive modulation techniques kits at your doorstep. You can learn from experts, build latest projects, showcase your project to the world and grab the best jobs. Get started today!
https://takeoffprojects.com/modulation-techniques
Modulation schemes used in wireless technologiesVijitaaDas
As we all know, in today's world, Wireless Technology is one of the most important method of communication between one device and other devices. This communication system uses a very clever technique called Modulation Technique or schemes to increase the reach of the signals. Another reason is to allow the use of smaller antenna. This PPT is mainly focused on the modulation schemes that helps in the communication process of Bluetooth, Zigbee, Wi-Fi and UWB.
A communication system is for transmitting and receiving the information that users want to exchange. To make up a communication system, we can adopt the FDMA, TDMA, CDMA, and so on. In this presentation, we introduce a simplified communication blocks with which we can understand a modern system.
Fundamental of Radio Frequency communications.pptginanjaradi2
Fundamentals of Radio Frequency (RF) communications encompass the principles and techniques used to transmit and receive information wirelessly using electromagnetic waves within the radio frequency spectrum. Here's a breakdown of the key components:
1. **Electromagnetic Spectrum**: RF communications utilize a portion of the electromagnetic spectrum. This spectrum ranges from low frequencies used for power transmission to high frequencies used in technologies like microwaves and beyond. RF typically occupies the frequency range from about 3 kHz to 300 GHz.
2. **Modulation**: Modulation is the process of impressing information onto a radio wave by varying one or more of its properties such as amplitude, frequency, or phase. Common modulation techniques include Amplitude Modulation (AM), Frequency Modulation (FM), and Phase Modulation (PM).
3. **Transmitters**: Transmitters generate radio frequency signals carrying the information to be transmitted. They typically consist of an oscillator to produce the carrier frequency, modulation circuitry to impress the information onto the carrier, and amplifiers to boost the signal for transmission.
4. **Receivers**: Receivers capture radio frequency signals, extract the desired information, and convert it into a usable form. Receivers include components such as antennas to capture the incoming signal, amplifiers to boost weak signals, demodulators to extract the information from the carrier, and filters to remove unwanted noise and interference.
5. **Antennas**: Antennas are crucial components for both transmitting and receiving RF signals. They convert electrical signals into electromagnetic waves for transmission and vice versa for reception. Antennas come in various designs optimized for different applications, such as dipole antennas, patch antennas, and parabolic antennas.
6. **Propagation**: RF signals propagate through the atmosphere, and their behavior is influenced by factors such as frequency, distance, terrain, and environmental conditions. Understanding propagation characteristics is essential for designing efficient communication systems.
7. **Propagation Models**: Propagation models describe how RF signals propagate in different environments. These models help engineers predict signal strength, coverage areas, and potential sources of interference. Common models include free-space path loss, multipath fading, and terrain-based models.
8. **Spectrum Management**: Since the radio frequency spectrum is a finite and shared resource, its allocation and usage are regulated by government agencies such as the Federal Communications Commission (FCC) in the United States. Spectrum management involves allocating frequency bands to different users, enforcing regulations to prevent interference, and promoting efficient spectrum utilization.
9. **Applications**: RF communications find applications in various fields, including broadcasting, telecommunications, wireless networking.
Interference issue between 3550 3700 m hz to domsat earth-station
1. Interference Issue between 3550-
3700 MHz to DOMSAT Earth Station
(C-band 3700-4200 MHz)
Eric Wong
Kawong_1999@yahoo.com
2. Possible Interference
CBS (TDD/FDD LTE WiFi) DOMSAT earth station receive
3700 42003650
Interference
20 MHz
Channel
LTE: 1.4 – 20 MHz Channel
WiFi: 20-80 MHz Channel
3. Problem Statement
• There are over 5,000 C-Band earth station licensed in the US.
• The out of band emission from transmitter operating in 3650-3700 MHz
will become in-band interference to 3700-4200 MHz (C-Band earth station
received frequency)
– Mostly for channel that are immediately adjacent to each others
– Mobile device will not be a concern due to the low transmit power
(40mw/MHz or 1w/25 MHz)
• Allowing signal to be transmitter in 3650-3700 MHz will be problematic for
incumbent C-Band earth station (assuming the distance is close between
each other)
• Interference signal can degrade signal quality or block service completely
• Many of the Earth Station today do not have the ability to integrate a filter
to increase the Adjacent Channel Selectivity
• In order to spectrum share, coordination is required.
• Exclusion zone will be required to protect the earth station from harmful
interference
4. 3GPP OOBE
• OOBE (out of band emission) is the unwanted
signal outside of the channel bandwidth resulting
from non-linearity in the transmitter (LTE, WiFi)
• 3GPP OOBE is define by ACLR
– ACLR = Adjacent Channel Leakage Ratio
– ACLR is the ratio of the filtered mean power centered
on the assigned channel frequency to the filtered
mean power centered on an adjacent channel
frequency
• Base Station ACLR = 45 dB
• Portable Device ACLR = 30 dB
5. Mitigation Methods
• Mitigation methods to ensure earth station are
protected from harmful interference cause by adjacent
channel (LTE, WiFi):
– Installing filters at the LTE, WiFi transmitter to reduce the
out of band emission
• That mean improve the ACLR of LTE, WiFi transmitter
– Installing filters at the earth station receivers to improve
adjacent channel selectivity
• Improve adjacent channel rejection
– Increase the separation distance between earth station
and LTE, WiFi transmitter
– Increase the guard band size between the two adjacent
chanel
6. Earth Station Receiver Interference to
Noise Specification
• According to ITU-R SF.1006, Co-channel Interference to Noise
(I/N) = - 10dB
• This means the Interference has to be 10 dB below the Earth
Station receiver system noise
• Earth Station system noise =
– kTB
• K = Boltzmann constant ~ 1.38 ∗ 10ିଶଷ ௨௦
• T = Temperature in Kevin ~ 111.72029 (see appendix)
• B = Bandwidth ~ 1 MHz
• kTB ~ -118 dBm ~ -148 dBW
• In order to meet the I/N of -10 dB, the Interference has to 10
dB below the system noise
– I= N- 10 dB
– -148 dBw – 10 dB = -158 dBW
7. Separation Distance Requirement
• Base on FCC 12-148 NPRM and Order, BTS are
limited to 25 watts per 25 MHz EIRP and the peak
EIRP power density shall not exceed 1 watt in any
1 MHz slice of spectrum
• Lets assume the 10 MHz LTE TDD system
• The peak EIRP will be 10 watts ~ 10 dBW
• The OOBE will be 10 dBW – 45 dBc = -35 dBW
• In order to meet the -158 dBW co-channel I/N
ratio requirement, pathloss of 123 dB ~ 9.3 km is
needed.
8. Separation Distance Based on Various
Earth Station Antenna Elevation Degree
No antenna pattern loss and 3GPP minimum requirement
9. Separation Distance Based on Various Earth Station Antenna
Elevation Degree with BTS Antenna Pattern Loss
Antenna has pattern loss depending on azimuth and elevation