FM Broadcast Research Articles

FM방송의 인접국 간섭환경에서 적응적 혼신보호비 변경에 의한 가용주파수 확보 방안

#9!FM:; !?) .@ABCD7E0FGHI1JJKDLMN12FGOPQRST;. UV*WXYZ0@[\]O2^_`aQD7EbFM!FG$c`200kHz()100kHzXdeDL, fgXhij(kl  AmnDoIBOC(In Band On Channel), DRM+(Digital Radio Mondial+) pq:rI1Ms;. htu#$4$%WXbvw`xyz({s;. |( )o1986 }!,- .(b J`4~DL,  vw €!B{O‚!DSP(Digital Signal Processing) 7ƒ(„ †,- .A710 ‡ˆ7*WX‰ŠDo5 `CD‹;. hŒLŽO\() $‘e34Oc’`800()400“o600Xde”WX•‚ -;2mq:12FG` -yMo1–—`˜™D‹;.AbstractThe channels of domestic FM broadcast are needed to provide various kinds of new broadcasting services. However, available channels are limited and saturated. The channel interval of FM broadcast is changed from 200 kHz to 100 kHz to maximize utilization efficiency of scarce broadcast spectrum at all over the world. Also, there are many researches such as IBOC(In Band On Channel) and DRM+(Digital Radio Mondial+) that is to allocate the digital signal beside analog bandwidth. But output power is decrease to avoid interference between adjacent radio stations. In this paper, we analyzes the problems of the protection ratio which is decided in 1986 and we propose method to improve about 710dB significantly the protection ratio according to the recent DSP(Digital Signal Processing) techniques without loss of both transmission power and broadcast quality. In addition, we examined the possibility of securing two times available channels by reducing minimum frequency interval from 800 kHz to 400 kHz or 600 kHz in the equal site.Keywords : Adaptive protection ratio, Available frequency, FM broadcast , Secure, Minimum frequency interval.

CALCULATION OF WHOLE-BODY SAR FROM A 100 MHZ DIPOLE ANTENNA

This paper presents results of a dosimetry study at an FM broadcasting frequency of 100MHz. The work focused on SAR calculations with high resolution Magnetic Resonance Imaging (MRI)- based full-body models. FDTD computer modeling used a half-wave dipole as the exposure source. Extensive calculations give the variation of SAR with distance and show that whole-body average SAR exhibits a difierent distance dependency from the incident power density. Body size has a signiflcant efiect on SAR. Based on the numerical results, an empirical formula was developed to describe the relationship between antenna input power and distance for the limiting SAR value.

SMATV를 위한 MATV/위성 방송 통합형 증폭기 개발에 관한 연구

최근 국내에서는 MATV(Master Antenna Television: 텔레비전 공동시청 설비)를 SMATV(Satellite Master Antenna Television)로 개정함에 따라 공동주택의 방송설비는 지상파 방송, FM 라디오 방송과 함께 위성방송을 의무적으로 통합하여 전송하도록 개정하였다. 국외의 경우 대부분의 나라에서 SMATV가 기본적으로 허용된데 반해 국내에서는 케이블 방송과 위성방송 서비스 업체간의 이익 분쟁으로 인해 SMATV용 혼합형 증폭기에 대한 기술 개발 및 양산이 미진한 상태에 있다. 따라서, 본 연구에서는 지상파 텔레비전 방송대역(54~806Mhz)과 FM 라디오 방송대역(88~108Mhz) 뿐만 아니라 위성방송 대역(950~2150Mhz)까지 증폭할 수 있는 광대역 증폭기를 개발하고 그에 따른 문제점의 해결방안을 제시한다. Recently n Korea, the House of Commons and terrestrial broadcasting facilities integrated with FM radio and the satellite compulsory was amended to transfer MATV(Master Antenna Television) adjusted by SMATV(Satellite Master Antenna Television). While the SMATV was accepted by default in most other countries, our county did not accept it as the default for broadcast. Because domestic cable and satellite television service providers are conflicts with their interest. bAs a result, the hybrid amplifier for SMATV technology development and volume production for the state is insufficient. Therefore, terrestrial television broadcast bands (54 ~ 806Mhz) and FM radio broadcast band (88 ~ 108Mhz) band satellite with (950 ~ 2150Mhz) to amplify the development of a broadband amplifier with subsequent resolution of problems is also presented in this study.

워터마킹 기법을 이용한 FM-VMS 설계 및 구현

In this thesis, Traffic information which is provided to the VMS used a FM frequency and provides real-time traffic information about the mobile production unit system which designed and produced and a quality evaluated. Result of the research, we will be able to confirm converted audio and text information from traffic information is linked with VMS information, FM broadcast traffic information to motorists passing through it were found to be and as a result of this study, which sees raises the effectiveness of VMS users and using VMS to build low-cos transport infrastructure will be an opportunity.

Digital Audio Around the World

DR (or DAB) has been around for several decades but only now is it being adopted and implemented by the commercial broadcast community. There are four types of systems: Eureka 147, DRM, IBOC, and Satellite Digital Audio Radio. There are two types of implementation strategies: use of dedicated spectrum and reuse of existing spectrum for AM and FM broadcasting. Eureka 147 uses dedicated spectrum; DRM and IBOC reuse existing spectrum. In addition, SDAR makes use of terrestrial as well as satellite systems (XM and Sirius). Digital tuner costs vary from US$150.00 to US$1,000.00. Table 3 shows a comparison of each type of system. Although a principal purpose of DR is the enhancement of audio quality, this technology offers additional features such as the ability to integrate and broadcast text, data, and video, weather service information, and satellite maps of your location. In addition, DR technology is adopting the use of software to defined radio capabilities and features that will result in longer equipment life cycles and using common equipment in diverse applications.

A Review of and New Results for Broadband Antennas for Digital Terrestrial Broadcasting: The Modified Batwing Antenna

Digital terrestrial broadcasting services are in the Japanese UHF band of 470 to 770 MHz. The bandwidth of the UHF-TV channel is 6 MHz. The batwing radiator, which is at the heart of the super-turnstile antenna system for FM and VHF-TV broadcasting, has broadband characteristics. In this paper, we investigated a modified batwing antenna for UHF digital terrestrial broadcasting. The characteristics of the two- and four-element modified batwing antennas, with an infinite or a finite wire reflector, were calculated using NEC-WIN Pro. We evaluated the characteristics of these antennas in the Japanese UHF-TV broadcasting band. A broadband input impedance and high gain were obtained in the calculation and the measurement. A four-plane arrangement of parallel batwing antennas was also examined for directionality. The batwing element was arranged in parallel, and the feed interval was a half-wavelength. High gain and wideband characteristics were obtained with simple power-supply construction. This antenna has sufficient characteristics for use as the transmitting antenna for digital terrestrial broadcasting stations and repeater stations in the Japanese UHF band.

High Power Wideband Class-E Power Amplifier

This letter shows a high-power, high-efficiency, wideband Class-E RF power amplifier designed upon the load admittance synthesis concept and built using an uncomplicated low-loss load network with a low loss wideband admittance transformer as the main component. It uses a power Silicon LDMOS transistor to provide up to 145 W at 28 V peak power, up to 86% drain efficiency over 35% fractional bandwidth (from 85 to 120 MHz) and 15.6 dB gain at peak power without any adjustments. These are clear performance advantages over previous published works and commercially available amplifiers at a similar frequency band and power level. The amplifier applications include FM broadcast, aeronautical communications, nuclear, MRI, heating or RF power stage for Envelope Elimination and Restoration transmitters.

Early FM radio: incremental technology in twentieth-century America

The commonly accepted history of FM radio is one of the twentieth century's iconic sagas of invention, heroism, and tragedy. Edwin Howard Armstrong created a system of wideband frequency-modulation radio in 1933. The Radio Corporation of America (RCA), convinced that Armstrong's system threatened its AM empire, failed to develop the new technology and refused to pay Armstrong royalties. Armstrong sued the company at great personal cost. He died despondent, exhausted, and broke. But this account, according to Gary L. Frost, ignores the contributions of scores of other individuals who were involved in the decades-long struggle to realize the potential of FM radio. The first scholar to fully examine recently uncovered evidence from the Armstrong v. RCA lawsuit, Frost offers a thorough revision of the FM story. Frost's balanced, contextualized approach provides a much-needed corrective to previous accounts. Navigating deftly through the details of a complicated story, he examines the motivations and interactions of the three communities most intimately involved in the development of the technology-Progressive-era amateur radio operators, RCA and Westinghouse engineers, and early FM broadcasters. In the process, Frost demonstrates the tension between competition and collaboration that goes hand in hand with the emergence and refinement of new technologies. Frost's study reconsiders both the social construction of FM radio and the process of technological evolution. Historians of technology, communication, and media will welcome this important reexamination of the canonic story of early FM radio.

Design of Stereo Frequency Modulation Exciter Controlled by Microcontroller

A new stereo Frequency Modulation exciter scheme for short-distance wireless communication is proposed. It adopts a stereo FM IC BH1415 to transmit audio FM signals, and its transmitting frequency is controlled by microcontroller. The basic principle of phase-locked loop for FM is analyzed, and the audio FM circuit based on BH1415 and the controlling method based on AT89C51 are introduced. Test results indicated that, the audio FM Exciter had simple structure and higher reliability, each parameter can meet the demands of FM broadcasting system, and it has some scalability.

Interference to DTV reception from FM radio signals

Interference to DTV reception from signals in the 88-108 MHz FM broadcast band has been observed since the end of analog TV broadcasting in June, 2009. This interference is generated in the front-end (tuner) of the affected receiver. This paper describes the non-linear mechanisms in the receiver by which FMI to DTV reception takes place. The author has tested 15 models of NTIA approved DTV down-converters measuring the increase in DTV received signal power required as a function of the power of local off-air FM signals in his laboratory. He has also tested "amplified indoor antennas" and found their performance was seriously impaired by FMI. This work was carried out as unsponsored research.

Multi-functional vehicle mount antenna system using magnetic coupling for FM/TDMB/PCS applications

A new multi-functional vehicle antenna, consisting of LNA-integrated non-uniform helical antenna for both FM and terrestrial digital multimedia broadcasting (TDMB) operation, and a monopole antenna for the PCS operation is proposed. The proposed architecture combines the three antennas in such a way as to maximum the reuse of the antenna structure and, thereby, reduces the overall antenna size. To realize a single-port excitation of three different band antennas, the PCS antenna and FM antenna is simultaneously excited with the help of steel stud while the TDMB antenna is magnetically coupled from a portion of the FM antenna body.

Embroidered Wearable Multiresonant Folded Dipole Antenna for FM Reception

A wearable textile antenna with multiple resonance frequencies is proposed for the reception of FM signals using conductive embroidery of metal composite embroidery yarn (MCEY) on a polyester woven substrate. This embroidered FM antenna comprises five individual folded dipoles connected in parallel so that the bandwidth can be broadened via multiple resonances. The MCEY embroidered multiresonant folded dipole (MRFD) antenna is attached to a jacket, stretched from the left forearm, over the shoulder, and to the right forearm. The proposed antenna provides a wide operating band of 80.5 MHz to over 130 MHz at 5 dB return loss regardless of the arm movements, satisfying the FM broadcast band (87.5-108 MHz). The gain of this body-worn antenna is in the range of - 7.08 to - 15.79 dBd in the FM broadcast band regardless of the arm movements.

Synchronization Receiver for OFDM-Based FM Broadcasting Systems

The digital radio mondiale (DRM) consortium is now preparing to test and verify the design of DRM plus, prior to standardization, produce a revision to the existing DRM system specification. This p...

Sounds of Change: A History of FM Broadcasting in America by Sterling, Christopher, and Michael Keith

<i>Sounds of Change: A History of FM Broadcasting in America</i> by Sterling, Christopher, and Michael Keith

Introduction: Community media’s long march

The new generation of media technologies and the success of the so-called ‘Web 2.0’ platforms has put at the centre of academic and industry discussions the participatory potential of internet-based media. ‘Old’ participatory platforms, alternative and community using traditional broadcasting or print outlets, though, have a long history of close involvement of their audiences in practices that have put communities’ communicative needs at the centre of their everyday work and fought for the democratization of media systems. Despite their financial and organisational weaknesses as individual stations or projects, community media are being increasingly recognised as the third and distinct sector of broadcasting by recent policy and regulatory developments in Europe and across the globe. The contributions present in this issue present the opportunities and challenges that are characterising the sector at this time, as the switchover to digital broadcasting platforms, and the need of constant presence at the European Union and Council of Europe levels to make sure that community media are considered with equal dignity among other broadcasters in media policy debates. Practice-based accounts also show the contribution of community media to intercultural dialogue, an impressive range of interactions with civil society organisations present in their communities, and the potential of giving voice to local and diasporic communities through innovative combinations of FM and web-based broadcasting. Finally, this special issue also shows evidence of the important role that civil society plays in the production of situated knowledge along, and in collaboration with, ongoing academic research in this area of study.

FM 라디오 환경에서의 실시간 음악 판별 시스템 구현

본 연구에서는 GMM 기반의 음성/음악 판별 방법을 응용하여 FM 라디오 방송에서 순수한 음악 구간만을 판별하는 시스템을 구현하였다. 본 시스템에서는 음성, 음악, 광고 음악, 기타 여러 가지 사운드가 혼합되어 있는 오디오 방송 프로그램에서 순수한 음악만을 판별하여 자동으로 저장하고자 한다. 음악의 시작 부분과 끝 부분을 보다 정교하게 검출하고자 순수한 음악으로 판별된 구간의 시작 부분과 끝 부분에 대해 후처리 과정을 추가하였다. PC 환경에서 FM 라디오 방송을 이용하여 구현된 시스템을 실시간으로 테스트한 결과 우수한 성능을 보임을 확인하였다. 또한 SoC 구현을 고려하여 고정소수점 연산을 수행한 결과 3MIPS 이하의 적은 연산량으로 부동소수점 연산일 때와 동일한 결과를 얻을수 있었다. This paper proposes a Gaussian mixture model(GMM)-based music discrimination system for FM broadcasting. The objective of the system is automatically archiving music signals from audio broadcasting programs that are normally mixed with human voices, music songs, commercial musics, and other sounds. To improve the system performance, make it more robust and to accurately cut the starting/ending-point of the recording, we also added a post-processing module. Experimental results on various input signals of FM radio programs under PC environments show excellent performance of the proposed system. The fixed-point simulation shows the same results under 3MIPS computational power.

Delay Selection for Improved Frequency Estimation in OFDM-Based FM Systems with Cyclic Delay Diversity

In order to improve the synchronization performance of the OFDM-based FM broadcasting system, this letter addresses the problem of delay selection when the system uses a cyclic delay diversity (CDD) scheme. By proper selection of the amount of cyclic delay, an improved fine carrier frequency offset estimator is derived. By computer simulation, the proposed estimator is shown to benefit from properly chosen delay parameter and perform robustly.

An integrated on-line audio watermark decoding scheme for broadcast monitoring

This paper proposes an on-line audio watermarking system for broadcast monitoring. The designed watermark (WM) encoder is a nonlinear data adaptive system that performs perceptual embedding. It allows working at very low watermark-to-signal ratio (WSR) levels thus preserves the inaudibility. The developed decoder adopts wavelet de-noising for blind watermark extraction and it is capable of watermark decoding while establishing the synchronization between the transmitter and the receiver. Unlike the published watermarking schemes, it is shown that the introduced WM embedding scheme minimizes false alarm ratio by adaptively controlling the WSR. Furthermore it integrates synchronization and WM extraction into one processing step resulting in an on-line decoding scheme suitable to audio broadcast monitoring. The proposed system is robust to Digital-to-Analog (D/A), Analog-to-Digital (A/D) conversions, compression and noise as well as the attenuations that arise from FM broadcasting and acoustic transmission. Performance under Stirmak attacks is also reported. It is shown that error free transmission of 24 bps is achieved at around WSR?=??32 dB when the PSNR is around 50 dB. Granularity of the system is 0.6 s thus it is capable of tracking short audio clips i.e. commercials.

Digital Audio Broadcasting in Canada: Technology and Policy in the Transition to Digital Radio

This article presents an overview of digital radio policy in Canada in the period 1995 to 2005 and the attempt to implement the Eureka-147 Digital Audio Broadcasting (DAB) standard as the replacement technology for analog AM and FM broadcasting. Canada was an early adopter of this system, but unfavourable conditions have led it to largely abandon the approach in favour of a multiplatform system. The interaction between industry, government regulation, and broadcasting policy around digital radio reveals a complex situation of competing interests. Despite extensive regulatory intervention to protect Canadian interests, the pace of technological change and the dominant influence of U.S. interests have made the transitional path to digital radio even more uncertain than it was 10 years ago.

Study of detection performance of passive bistatic radars based on FM broadcast

Abstract The passive bistatic radar based on the FM broadcast has inherent superiority with respect to its survivability. In this article, the ambiguity function (AF) and the cross ambiguity function (CAF) of the FM radio signal are analyzed and illustrated. The Kolmogorov Smirnov (K-S) test verifies that the amplitude probability density function of the CAF side lobes is exponential; the distribution of the target is also deduced. Finally, the detection performance of the passive radar is studied, and the result shows that this new type bistatic radar has favorable detection capability.