FM Transmitter Research Articles

Strategi Pemasaran Radio Kardopa dalam Meningkatkan Minat Pendengar Muda di Kota Medan, Provinsi Sumatera Utara

Technological advances have recently become the concern of all human beings, especially with this broadcasting institution, Radio Kardopa 99.4 FM. One of the things that must be able to compete with the development of an era that is increasingly rapid in its growth is technology. Initially, this radio only distributed information in a traditional way, such as through accessing only FM transmitters. Which in this day and age is considered old-fashioned and less effective because not everyone is interested in listening to radio on a frequency transmitter. So a live streaming radio and social media platform was created to convey information. On this occasion, the author uses a digitalized marketing strategy using access to social media as an information distribution strategy. So wherever they are they will always be able to listen to their favorite radio. To increase its audience, the broadcaster has evaluated the strategy used. Where this broadcasting institution, namely Kardopa Radio itself, already has a Tiktok account which aims to increase listeners, namely young people or millennials and gen-z. This is done because Kardopa Radio knows very well that information does not only belong to certain groups, but belongs to all groups, including the young people. It can be seen from the follower insight data that many follow the @radiokardopa.kdigi account, the age of 25-34 is 39.0% and the age of 18-24 is 32.0%. It is clear that the target to be achieved has been accomplished during the author's internship at this place. In this study the authors used a qualitative method with a descriptive case study approach, this aims to increase the interest of young listeners and is designed through an effective approach.

STARFIRE: An algorithm for estimating radio frequency interference in orbits around Earth

Ground-based 21-cm experiments targeting the global signal from the periods of Cosmic Dawn (CD) and Epoch of Reionization (EoR) are susceptible to adverse effects presented by i) the ionosphere ii) antenna chromaticity induced by objects in its vicinity iii) terrestrial radio frequency interference (RFI). Terrestrial RFI is particularly challenging as the FM radio band spanning over 88-108 MHz lies entirely within the frequency range of the CD/EoR experiments (∼40–200 MHz). Multiple space-based experiments have been proposed to operate in the radio-quiet zone on the lunar farside. An intermediate option in cost and complexity is an experiment operating in space in an orbit around Earth, which readily alleviates the first two challenges. However, the effect of RFI in Earth’s orbit on the detection of global signal needs to be quantitatively evaluated. We present STARFIRE – Simulation of TerrestriAl Radio Frequency Interference in oRbits around Earth – an algorithm that provides an expectation of FM seeded RFI at different altitudes over Earth. Using a limited set of publicly available FM transmitter databases, which can be extended by the user community, we demonstrate the use of the STARFIRE framework to generate a three-dimensional spatio-spectral cube of RFI as would be measured in Earth orbit. Applications of STARFIRE include identifying minimum RFI orbits around Earth, producing RFI spectra over a particular location, and generating RFI heatmaps at specific frequencies for a range of altitudes. STARFIRE can be easily adapted for different frequencies, altitudes, antenna properties, RFI databases, and combined with astrophysical sky-models. This can be used to estimate the effect of RFI on the detection of global 21-cm signal from Earth-orbit, and hence for sensitivity estimates and experiment design of an Earth orbiting CD/EoR detection experiment.

Eğitsel SDR Tekniklerine Dayalı FPGA Tabanlı FM Radyo Verici Tasarım ve Uygulaması

The basic purpose of Software Defined Radio (SDR) systems is to use a digital signal processor to numerically handle radio signals. The use of a processor like a Field Programmable Gate Array (FPGA) to perform tasks like modulation, demodulation, signal creation, and line coding on these systems dramatically decreases the demand for analog circuit-based hardware. FPGAs are digital integrated circuits with a wide range of applications which are made up of links between programmable logic blocks. It's aimed at assisting the creator realize the logic functions that the designer needs. In consequence, the user may change the function of each logic block. VHSIC Hardware Description Language (VHDL) is commonly used in FPGA programming. In this study, VHDL code was created, and a FM transmitter was implemented on a FPGA board (CMOD A7) in this research. The sound card interface on the PC used to send and receive the signals while suitable ADC and DAC cards are used on the FPGA side for the same purpose. Audacity program was used to playback the sample wav files while HDSDR SDR program was used to monitor and record the signals in wav file format. Finally, using the MATLAB code, the recorded transmitter signal was demodulated offline, and the output was stored to the hard drive. The demodulated signal obtained is identical to the initial modulation signal, indicating that the modulation was correctly executed. As a result, a perfect foundation for the development and training of SDR systems using FPGA has been established.

DRM DIGITAL BROADCASTING SYSTEM AUDIO PATH QUALITATIVE CHARACTERISTICS

The Digital Radio Mondiale (DRM) digital broadcasting system is the only ITU-approved digital broadcasting system for the LF, MF and HF bands. Numerous theoretical and field studies, as well as operating experience over the past 20 years, have allowed a good study of digital broadcasting networks organization according to this standard. However, some of the issues related to the audio path formal characteristics were not considered. The article discusses the audio coders used in the DRM system and the available data rates in various immunity modes. A set of test signals for instrumental measurements and listening has been developed. The results of experimental measurements for various data rates are presented. It is shown that the range of modulating frequencies in 7 modes of immunity is not narrower than for FM transmitters. In another 5 modes of noise immunity, the range of modulating frequencies is narrower than for FM transmitters, but wider than for AM transmitters. It is confirmed that at data rates of more than 16.5 kbps, the DRM transmitter signal quality becomes no worse than AM signal transmitter quality. Above 24 kbps, the DRM transmitter signal quality becomes comparable to that of an FM transmitter.

Uncued Detection and Initial Orbit Determination From Short Observations With the Murchison Widefield Array

This article details the latest developments in the use of the Murchison Widefield Array as a passive radar receiver for the surveillance of space. We cover methods developed to incorporate orbital parameters into matched-filter processing to achieve uncued detection without a prior track, and generate accurate detection-level initial orbit estimates. We present the results from a short collection campaign conducting broad surveillance stares, using FM transmitters as an illuminator with a significantly large bistatic baseline length of 600 km. Initial results demonstrate improved performance in the Murchison Widefield Array's detection of objects in typical low Earth orbital regimes, detecting objects with radar cross section of 1 m2 as well as the generation of accurate initial orbital estimates using very short arc detections spanning less than half a degree.

Real-time Water Level Monitoring Using IOT

This paper focuses on monitoring of the water level and its data visualisation. It provides real-time data recorded by the data logger.The key feature for measurement of water is its pH level .VFC320 monolithic voltage-to-frequency converter was used to find digital pulses and these frequencies have been multiplexed through frequency division multiplexing, modulated through FM generation, and transmitted through an antenna through an FM transmitter. The transmit frequency has been received by the FM receiver and separated by the frequency division demultiplexer. Samples analysis was done through MATLAB.When the water level goes up the variation on the spectrum shows up and vice versa.To find the water level, the Arduino Uno approach is used and broadcasting is done to get updated information. This study combined a model of simulation and optimization that could be used to help sustainable management-related decision making.

Drivers’ Warning Application Through Image Notifications on the FM Radio Broadcasting Infrastructure

In this paper a new application for transmitting image notifications on the FM radio broadcasting infrastructure, dedicated to warn drivers about significant road events and to increase the traffic safety is presented. The paper analyzes different technical solutions suitable for transmitting and receiving real-time image notifications in different scenarios by using the software-defined radio concept. In the first scenario, the image notifications are QPSK modulated and transmitted with 8 kb/s bit-rate by using a mono FM radio channel. In order to increase the speed of data transmission, the second scenario uses the FM subcarrier channels dedicated for broadcasting alternate services. In this case, a stereo FM radio channel is used to transmit data with 40 kb/s, 60 kb/s and 80 kb/s bit-rates, by using QPSK, 8-PSK and 16-PSK modulations, respectively. A new software solution to perform the real-time carrier synchronization for 8-PSK/16-PSK modulation based on a decision-directed PLL and non-linear decision block is also presented. The functionality of the proposed application was demonstrated by simulations for both transmission scenarios. Moreover, the first scenario was tested experimentally by using a professional FM transmitter and a simple RTL-SDR dongle as receiver. The customized baseband modulating signal including audio, data (image notification) and RDS signals was generated by using a device built by the authors. The receiver provides the digital signal through a USB interface to a software program, running on a processing unit, for demodulation. An experimental method for plotting the bit error rate vs. <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$E_{b}/N_{0}$ </tex-math></inline-formula> ratio, based on signal-to-noise ratio measured with a software spectrum analyzer is also proposed. This method allows the characterization of the data transmissions performed by using an experimental setup and give hints about the QPSK signal power level compared to the other ones (audio and RDS signals).

Analisa Certainty Factor Dalam Mendiagnosa Kerusakan Alat Pemancar Radio 87.6 Dass FM Lubuk Pakam

An FM transmitter or FM transmitter is a source of radio vibrations emitted by a device called an oscillator or oscillator. While the oscillator is a device that can produce high frequencies. The scope of this research is an expert system that is built only to discuss the symptoms and damage to radio transmitters and solutions to fix them. The resulting output is radio transmitter malfunction information and solutions to repair it. The programming language used in solving this problem is PHP by using the mysql database. The method used in solving the damage to the radio transmitter is the certainty factor method.

Design and Implementation of a Smart &amp; Portable Wireless FM Transmitter for Wide Range Communication

The evolution of smart technologies makes end users to choose portable, cost-effective and reliable devices for their daily life usage. The optimum service and superior quality of any such devices are always remain the centers of attraction for any customer. The advent of new technologies gives the smart FM transmitters also a unique shape. Depending on the dynamic requirements, the customer needs always changes with time. Keeping this fundamental issue in mind, in this work, we have designed and implemented a smart FM transmitter model keeping the key features in mind. Its small size, long battery life, and easy portability make it very useful to be used in day to day life. It has the potential of real-time noise cancellation features to get the optimum sound quality at the receiver end. The Digital Frequency Modulation Scheme has been used here to boost the signal strength for long-range communication. The used components are very cost-effective and reliable for prolonged use. The test case has given high-quality sound reception at the receiving end from the source end using our model. This smart transmitter section model has been found to be very effective for the future digital communication system. The specific station catching ability and low tone scanning capability make it superior to other existing similar kinds of devices. It can be used at home, or institutional premises, or any other distant trials for effective information exchange.

Digital FM Transceiver Design and Construction using Microcontroller and I2C Interfacing Techniques

Communication is very much important for every community and radio communication is one of the easiest and simple media to provide information. The project represents the full duplex communication mode of FM transceiver (Radio + Transmitter). This paper describes on how to build a short-range FM transmitter using microcontroller. The paper also describes on how to build a FM radio receiver using micro-controller. Through the FM transmitter we can transmit our voice and any audio signal while through the radio receiver listener can listen any FM broadcasting channel. This project is based on KTMicro IC KT0803K monolithic digital stereo FM transmitter and Phillips TEA5767 radio receiver module. The quality of transmission and radio reception can be improved by Digital Signal Processing and Intelligent Tuning System. The heart of this project is Arduino UNO micro-controller which controls slave devices by Inter-Integrated Circuit (I2C) communication. The transmitter and the receiver both supports digital tuning and Phase Locked Loop (PLL) concept is used for recovery of the signals. The transmitter of this digital FM transceiver can be used for making announcements in schools, colleges, industries, hospitals, and other places using a condenser mic amplifier circuit and share music with the FM listeners using audio input port of the FM transmitter module. The radio receiver of this transceiver is used for listening any local FM broadcasting channel. It can be also used in specialized application such as local area network. For the construction of the transceiver it requires some small and low cost external equipment’s.

Analysis of automatic monitoring system for all solid state FM transmitter

All-solid FM transmitter; The computer; Automatic monitoring

A low-frequency blind survey of the low Earth orbit environment using non-coherent passive radar with the Murchison widefield array

AbstractWe have extended our previous work to use the Murchison widefield array (MWA) as a non-coherent passive radar system in the FM frequency band, using terrestrial FM transmitters to illuminate objects in low Earth orbit (LEO) and the MWA as the sensitive receiving element for the radar return. We have implemented a blind detection algorithm that searches for these reflected signals in difference images constructed using standard interferometric imaging techniques. From a large-scale survey using 20 h of archived MWA observations, we detect 74 unique objects over multiple passes, demonstrating the MWA to be a valuable addition to the global Space Domain Awareness network. We detected objects with ranges up to 977 km and as small as$0.03$${\rm m}^2$radar cross section. We found that 30 objects were either non-operational satellites or upper-stage rocket body debris. Additionally, we also detected FM reflections from Geminid meteors and aircraft flying over the MWA. Most of the detections of objects in LEO were found to lie within the parameter space predicted by previous feasibility studies, verifying the performance of the MWA for this application. We have also used our survey to characterise these reflected signals from LEO objects as a source of radio frequency interference (RFI) that corrupts astronomical observations. This has allowed us to undertake an initial analysis of the impact of this RFI on the MWA and the future square kilometer array (SKA). As part of this analysis, we show that the standard MWA RFI flagging strategy misses most of this RFI and that this should be a careful consideration for the SKA.

A survey of spatially and temporally resolved radio frequency interference in the FM band at the Murchison Radio-astronomy Observatory

AbstractWe present the first survey of radio frequency interference (RFI) at the future site of the low frequency Square Kilometre Array (SKA), the Murchison Radio-astronomy Observatory (MRO), that both temporally and spatially resolves the RFI. The survey is conducted in a 1 MHz frequency range within the FM band, designed to encompass the closest and strongest FM transmitters to the MRO (located in Geraldton, approximately 300 km distant). Conducted over approximately three days using the second iteration of the Engineering Development Array in an all-sky imaging mode, we find a range of RFI signals. We are able to categorise the signals into: those received directly from the transmitters, from their horizon locations; reflections from aircraft (occupying approximately 13% of the observation duration); reflections from objects in Earth orbit; and reflections from meteor ionisation trails. In total, we analyse 33 994 images at 7.92 s time resolution in both polarisations with angular resolution of approximately 3.5$^{\circ}$, detecting approximately forty thousand RFI events. This detailed breakdown of RFI in the MRO environment will enable future detailed analyses of the likely impacts of RFI on key science at low radio frequencies with the SKA.

Frequency Modulated Parametric Oscillation for Antenna Powered Wireless Transmission of Voltage Sensing Signals.

Wireless transmission of voltage signals are particularly useful for sensors embedded inside a closed environment where long-term operation without internal batteries is desirable. For this purpose, voltage tuning resonators can be used, because their voltage-dependent frequency responses can be contactlessly characterized by loop antennas connected to the output and input ports of a network analyzer. However, such passive sensors have limited remote detectability and temporal resolution, especially for smaller frequency shifts that would require repetitive averaging for acceptable measurement accuracy. To overcome these limitations, a double frequency parametric resonator is inductively coupled with a voltage tuning resonator to convert resonance frequency shifts of the passive sensor into frequency encoded oscillation signals that can be instantaneously detected over larger distance separations. This antenna powered FM transmitter has a compact design to achieve good voltage sensitivity and linearity, making it potentially useful for multiple applications from PH sensing to electrophysiological recording.

PENGIRIMAN TEXT MELALUI GELOMBANG FM BERBASIS ARDUINO UNO

There are many devices that can be used to communicate, where communication is information that can be conveyed in the form of data, news or messages in the form of symbols / signs, writing, pictures, or sounds. This study aims to create an alternative device by utilizing FM radio waves, the text sent by FM Transmitter will be received and processed into text and displayed on the LCD on the side of the receiver. As input is used Keyboard PS / 2, Arduino Uno with ATMega328P Chip IC to process data, FM Transmitter as a signal sender ,FM Receiver and LCD to receive and display text. The results show that text can be sent and received well when in and outside the room. Outdoor text can be sent and received well within a distance of ≤35 meters with room temperature of 27 degree Celcius, and in the room text can be sent and received well within a distance of ≤37 meters with room temperature of 25 degree Celsius. Temperature can affect the quality of the signal sent and received by the FM radio, so that outside the text can be sent and received well within a distance of ≤26 meters with 61 degree Celsius temperature.

Development of Space-based IOT terminal for Nanosatellite UiTMSAT-1

This paper presents the development of space-based IOT terminal for Store and Forward (S&F) mission of nanosatellite UiTMSAT-1. The function of this ground terminal is to collect data from the sensor and send the data to the satellites over VHF amateur radio frequency band. In this case, the satellite is replaced by dummy S&F payload. To send the data from the terminal to satellite, a concept of communication in an amateur radio network is adapted. In an amateur radio network, the communication is done by a special microprocessor system called Terminal Node Controller (TNC) which implement a special protocol called AX.25 protocol. The hardware involves the development of the terminal are Control and Communication Unit (CCU) and Very High Frequency (VHF) Transceiver. CCU function as a device that collects the data from the sensor and sends the data to the VHF Transceiver, while VHF Transceiver function as a device that does the data processing before sending them to the satellites. The VHF Transceiver is built-in with TNC, AFSK Modulator, and FM transmitter. With the current setting, the total bytes allowed for sending the data packet to the satellite are 175 bytes with speed of 1200 bits per second. The data packet that was successfully received by the dummy S&F payload can be validated by using terminal emulator communication program such as real-term, here the data packet that is received by the dummy S&F payload will display on the real-term display terminal. The transmitting data from the proposed ground terminal that are successfully received by the dummy S&F payload can be seen at terminal emulator program (Real-Term).

BELA transmitter performance and pointing stability verification campaign at DLR-PF

BELA is the first European planetary laser altimeter and shall be launched onboard of ESA's Mercury Planetary Orbiter (MPO) as part of the BepiColombo spacecraft in October 2018. The complete development of the instrument was done in collaboration with team members in Switzerland, Germany and Spain. The transmitter is also the first space-qualified laser system for a planetary mission built in Europe. Highly important for scientific performance is the transmitter's performance which is specified with demanding values. Thermo-optical pointing stability, alignment, pulse energy, wavelength, pulse profile and length have a direct impact on the signal quality and strength of the instrument and in consequence on the quality of science data. Furthermore for in-orbit operation the detailed knowledge of the transmitter behavior is required for the interpretation of measurement data. Therefore the transmitter, an encapsulated diode pumped pulsed Nd:YAG laser, was extensively tested at facilities at DLR in Berlin-Adlershof under various environmental conditions in all possible representative configurations. This is necessary because thermo-elastic and optical behavior are difficult to predict accurately only theoretically. Furthermore there are temperature dependent effects, e.g. for laser energy, which directly affect science measurements and can only be calibrated on-ground. An optical test bench was designed and set up for this particular task. This work describes the test bench and the measurement procedures. The measurement results for the Engineering Qualification Model and Flight Model are presented and discussed as well as lessons learned. The outcome of the tests shows that the BELA FM transmitter performs well with margins and BELA is expected to achieve its scientific goals.

Measuring willingness-to-pay for mobile phone features: a multi-region study

Measuring willingness-to-pay for mobile phone features: a multi-region study

Investigation of Diurnal Variation of Signal Strength Generated by FM Transmitter

This paper focuses on the determination of the diurnal variation of signal strength generated by Orient 94.4 FM transmitter along six (6) selected route in Imo State, Nigeria. This was carried out with the aid of a constructed signal strength meter (SSM). Signal strength measurements were collected at different time, on different days, and in different months. The measurement was carried out at a constant distance of 20 Km. Arrangement was made with the management of the base station to ensure that the transmitting parameters were kept constant throughout the period of signal strength measurement. The average results of these measurements were taken. The data obtained from the measurements was plotted in a graph to establish the diurnal variation in signal strength along the different routes of signal strength measurement. It was observed from this research that transmission and reception of signals are dependent on the time of the day. High signal strength was noted between the hours of 8 am and 11 am, while low signal strength was recorded between the hours of 1 pm and 5 pm. Better signal strengths were recorded at night. The result of this study shows that signal strength generated by FM transmitter vary with time of the day and the prevalent weather conditions. Stronger signals are recorded mostly at night along the different routes of the study. The signal strength consequently drops in the afternoon and recovers in the morning hours.

The design of the CNC FM transmitter

The design of the CNC FM transmitter