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Curs Nr. 7 28 /11/2008

Curs Nr. 7 28 /11/2008. Entertainment Radio Basics. Emilian Mariniuc. Content. What does this presentation contains? Following slides are related to Radio Basics and also few things about Media Player. What is not in the scope of this presentation?

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Curs Nr. 7 28 /11/2008

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  1. Curs Nr. 728/11/2008 Entertainment Radio Basics Emilian Mariniuc

  2. Content • What does this presentation contains? • Following slides are related to Radio Basics and also few things about Media Player. • What is not in the scope of this presentation? • This presentation will not contain projects specific communication protocols or implementation code.

  3. A little bit of history • The first extended broadcast of the human voice was transmitted through the air on December 24, 1906 from Brant Rock, Massachusetts by Reginald Fessenden, a Canadian engineer • In 1930, the Galvin Corporation introduced one of the first commercial car radios, the Motorola model 5T71. • In Germany Blaupunkt fitted their first radio to a Studebaker in 1932 and in the United Kingdom Crossley offered a factory fitted wireless in their 10 hp models from 1933.

  4. Contents • A little bit of history • Entertainment Radio • (FM) Radio Data System • (FM) Radio Jobs • EON • AlternativeFreq • Radio • Noise Calculation Alghoritm • DAB • SDARS • Media Player • Brief

  5. FM (Frequency Modulation)/AM (Amplitude Modulation) Signal Modulation AM Signal Modulation FM Animation

  6. Fm Radio(Radio Station Reception quality definition) • Distance between broadcast and reception unit The radio signal strength is directly link to the distance between the broadcast station site and the reception unit. In case of mobile reception, the reception quality is improve when the distance become shorter and worst when the distance is increase. • Obstacle stands in the way. The radio signal strength is reduced in case of an obstacle stands in the way of the wave. E.g: trees, Buildings, Hills, Mountains, Tunnel... In case of mobile reception, the reception quality is decrease when the reception unit move into a reception shadow area due to an obstacle.

  7. Fm Radio(Radio Station Reception-Field strength) • It is the amplitude of the received radio station signal carrier • The signal strength is directly influenced by : • The broadcast Station Characteristic • The broadcast signal propagation • Broadcast station and the reception unit localisation • Reception Unit Performance

  8. FM Radio - Algorithm for calculating noise • Algorithm for calculating noise within one quarter of the band • Assumption for a working noise calculation is a linear band scan process. • The algorithm measures the difference between the field strength of two adjacent frequencies. The result of this difference is limited by the parameter TUNNEL_FS_DIFF_LIMIT (default 15). The absolute value of this result is added to a sum only if the sign of the result has changed since the last calculation.

  9. FM Radio - Algorithm for calculating noise int diff_sum = 0; //summed differences of FS within one band quarter int sign_fs_diff = 0; //1 for positive, 2 for negative for (trans_index = first_trans_in_quarter+1; trans_index <= last_trans_in_quarter; trans_index++) { int diff_fs =0; if (get_fs(trans_index) > get_fs(trans_index-1)) { if (sign_fs_diff != 1) { sign_fs_diff =1; diff_fs = get_fs(trans_index) - get_fs(trans_index - 1); } }else if (get_fs(trans_index - 1) > get_fs(trans_index)) { if(sign_fs_diff != 2) { sign_fs_diff = 2; diff_fs = get_fs(trans_index -1) - get_fs(trans_index); } }else { sign_fs_diff = 0; diff_fs = 0; } if (diff_fs > TUNNEL_FS_DIFF_LIMIT) { diff_fs = TUNNEL_FS_DIFF_LIMIT; } diff_sum = diff_sum + diff_fs; }

  10. Block D Block A Block B Block C Data 16B Check 10B (RDS) Radio Data System 1 RDS Group = 4 Blocks = 104 Bits • The RDS group consists of 4 data blocks • Each block comprises an information word and a check word • Each information word comprises 16 bits • Each check word comprises 10 bits • Blocks are transmitted in the following order A, B, C and D

  11. Block D Block A Block D Block D Data 16B Check 10B RDS (Radio Data System) Group Type/Version/.... PI CODE • The first four bits of specifies the application of the group • Groups are referred as types from 0 to 15 • For each group two versions are possible • The version is specified in the fifth bit

  12. RDS (Radio Data System) • Program Identification [PI] • Program Service Name [PS] • Program Type [PTY] • Traffic Announcement [TA] • Clock time [CT] • Music/Speech [M/S] • Radio Text [RT] • Traffic Message Channel [TMC] • Alternate Frequency [AF] • Extended Other Network [EON] 106.5 MHz Europa Fm TP News 9:45

  13. A 6 F E 2 7 9 9 2 C C F 8 3 6 D 2 6 5 F 0 : Local 1 : International 2 : National 3 : Supra Regional 4: .. Regional F : A 4 B E 5 F D 8 E 8 3 1  RDS (Radio Data System)-Station Identification PI CODE(16bits) Coverage Area Country Code Reference Number b15 b11 b7 b0 F098 7112 C203,F201 D311,6321 C421,D4A2 FE46, PI Code is the unique code that identifies the station. Every station receives a specific code with a country prefix.

  14. RDS (Radio Data System)- Program Service Name • Allows user to identify the tuned station. It is a 8 characters string defined by the broadcast radio station. • Normally, it is used for : • Display the Name of the currently listen to station . • Access to next/previous station by alphabetical name order. • Create Stations list sorted by alphabetical order. 98.8 , PI : C201 , PTY : 10 , PS : “BBC R1 “ 89.1 , PI : C202 , PTY : 9 , PS : “BBC R2 “ 91.3 , PI : C203 , PTY : 14 , PS : “BBC R3 “ 93.5 , PI : C204 , PTY : 1 , PS : “BBC R4 “ 94.9 , PI : C411 , PTY : 12 , PS : “BBC GLR”

  15. AF1 / AF2 Length 91.7 92.0 90.7 89.2 93.8 92.9 99.4 91.9 91.5 93.0 97.1 Length 91.7 RDS (Radio Data System)- Alternative Frequency (AF) • Alternative Frequency (AF)This feature, an automatic tuning to the best received frequency feature. 91.7 , PI : F203 , PS “MUSIQUE “ Surrounding frequencies 92.0Mhz 97.1Mhz 90.7Mhz 93.8Mhz 89.2Mhz 92.9Mhz 99.4Mhz 91.5Mhz 91.9Mhz 93.0Mhz 99.4 92.0 92.9 91.7 89.2 89.7 93.8 90.7

  16. RDS (Radio Data System)- Radio Data Text This function allows a radio station to transmit a 64-character free-form textual information that can be either static e.g. station slogans or in sync with the programming such as the title and artist of the currently-playing song. EuropaFM...106,5...

  17. RDS (Radio Data System)-EON(Enhanced Other Networks ) • This function allows to transmit data of another radio. If this function is used and activated the receiver can commute temporarily to receive data on the road traffic for example and return automatically to the originated radio at the end diffusion of these data. This function uses the group 14A. BBC R1 PI : C201 PS " BBC R1 " TP 0 TA 1 PTY 9 AF List [...] • EON-PI • EON-PS • EON-TP • EON-TA • EON-AF • EON-PTY BBC R4 PI : C204 PS " BBC R4 " TP 0 TA 1 PTY 24 AF List [...] BBC R2 PI : C202 PS " BBC R2 " TP 0 TA 1 PTY 9 AF List [...] BBC R3 PI : C203 PS " BBC R3 " TP 0 TA 1 PTY 24 AF List [...] BBC GLR PI : C411 PS " BBC GLR " TP 1 TA 0 PTY 10 AF List [...]

  18. DAB (Digital Audio Broadcast)-DAB and FM/AM compared Fm: different frequencies, large spectrum, few stations Dab: multiple audio streams onto a single broadcast frequency called a DAB ensemble The original objectives of converting to digital transmission were to enable higher fidelity, more stations and more resistance to noise

  19. DAB (Digital Audio Broadcast) • DAB radios automatically tune to all the available stations, offering a list of all stations. • Using Band III and L-Band Transmitters • One Ensemble can carry more services (audio and data) • Primary audio service can carry secondary service. • Audio quality depending on used Codec • "Gleichwellen betrieb" – 2 Transmitter with same ensemble can operate on same frequency – improved quality • No FM-like Follow-me within one ensemble

  20. DAB (Digital Audio Broadcast)-Germany • Since over 10 years in Germany but not very successful • In Hessen only 4 programs (DRadio, DLF, Harmony (mono), HR-Info (low bit-rate), Planet (mono) • Many stations using channel 12A-F have only reduced power (1 kW), because of neighbor channels used by Bundeswehr. • In other countries (UK) are more DAB stations available.

  21. Satellite Radio Technology

  22. SDARS (Satellite Digital Audio Radio Service) -Technology • Two providers for SDARS Radio in U.S.A: XM & Sirius • XM: two high-powered satellites in geostationary orbit above the equator in addition to a network of ground-based repeaters • Currently, its three satellites fly in geosynchronous highly elliptical orbit (Tundra orbit) in a 24-hour orbital period • On February 19, 2007, XM announced a merger deal with Sirius Satellite Radio. The merger combined the two radio services and created a single Satellite Radio network in the United States and Canada. • Receiver: At the heart of a Sirius receiver is a custom application specific integrated circuit (ASIC) chip called the Baseband Integrated Circuit currently the STA240, which is produced by STMicroelectronics

  23. SDARS - Satellite Radio - Technology • Programming: over 100 channel • Over 40 channels commercial free music • Over 50 channels news, personality, specialty, premier sports, talk radio, comedy, children's and entertainment programming • Major metropolitan traffic information and weather forecast • Rear Seat Mobile Video (Sirius) • Service First Launched – 2001 • Both are Subscription based service: ~ $12.95 / month • U.S. continental coverage including Canada • Over 8,250,000 XM and 7,900,000 Sirius subscribers as today

  24. Media Player iPod, USB Stick ... Radio Navigation Mobile phone connectivity Audio Player Video Player

  25. Media Player Concept The MediaPlayer allows playback of compressed audio files (MP3, WMA), audio CDs (CD-DA) and content from connected media devices (iPod, Zune, MTP (Media Transport Protocol), ...) The MediaPlayer provides possibilities to access media content either by file system structure or by metadata (genre, album, artist, ...)

  26. Brief • If you have to describe this presentation in one word, what would that word be? Radio • Which is the protocol used for decoding FM radio signal? RDS • Can you name a difference between DAB, FM and SDARS? Fm-analog signal, DAB- digital, SDARS Satellite Radio • Name two devices that can be played by media player. Ipod, Zune

  27. References • http://en.wikipedia.org/wiki/Digital_audio_broadcast • http://en.wikipedia.org/wiki/IBOC • http://en.wikipedia.org/wiki/SDARS

  28. The End . Thank you for your attention...

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