HD Radio Toolbox. Nautel Ltd. User s Group

Transcription

1 HD Radio Toolbox (-14/-10 Solutions) Nautel Ltd. User s Group Mike Woods Head of Development Hal Kneller CPBE Market Development Manager

2 Getting to -14/-10 Agenda Designs leading to where we are now in HD Radio technology Reliable HD Transport review HD PowerBoost What is it What does it do? Asymmetric Sideband Operation Other options outside of transmitter power increase Recap on what helps/hurts transmitter de-rating

3 Why An HD Radio Power Increase? Better building penetration Reliable outdoor coverage to 60 dbu contour or beyond (less blending or multicast dropouts) Better reception on portables Early talk of this prompted Nautel engineers to start thinking about best practices going forward

4 Some Nautel Tool Box Firsts First HD Radio equipment manufacturer to engage true dynamic pre-correction (2004) As Exgine was developed, we noted loss of a single UDP packet punched a 1.4 sec. hole in the IBOC audio Developed Reliable HD Transport as a means to resend dropped or damaged packets (2007) Elevated sideband power operation (-13) demonstrated in Kiev, Ukraine (2007) Concept of enhanced PAPR shown at NAB (2008) Asymmetric IBOC sideband power shown to customers under NDA (2009)

5 How Much Injection is Enough? Analyze your digital coverage High noise environment? Coverage needed? Interference to other stations? Interference to your own analog? Regulatory clearance beyond -14? Consultants can help -15dB -16dB -14dB -12dB? -13dB -10dB

6 Reliable Transport Improves reliability by smoothing out the HDC E2X data, reducing burst requirements Permits re-transmission of lost/damaged packets via IP back-channel Before Reliable Transport (E2X connection) After Reliable Transport (E2X connection)

7 Efficiency vs. Injection Level Common Amp (Low Level) Efficiency Nautel NV Series 65.0% 60.0% 55.0% 50.0% 45.0% 40.0% 35.0% 30.0% 88 Mhz 98 Mhz Injection Level

8 Transmitters: Higher Injection Implications Limitations: Linearity (spectral mask) Thermal dissipation Most transmitters using dynamic pre-correction today are thermally limited

9 HD Power Boost A Nautel innovation which applies PAPR techniques to the entire transmitted signal. More digital power (Up to 30% Substantially higher efficiency (up to 7%) Upgraded hardware for NVE exciters. Optional software suite implemented in NVE Typical ROI less than 2 years Availability Q3 2010

10 HD PowerBoost: Hardware implementation Our demonstration at NAB 2009 used a very high power 8-core industrial PC NV Series Exciter (Current Implementation In FPGA)

11 Standard PAPR Reduction Algorithm Operation works on IBOC signal only signal clipping magnitude is clipped at a threshold phase angle is maintained resultant symbol is demodulated effects of clipping are corrected performs 2048 point IFFT re-applies pulse shaping function iterative algorithm all carriers constrained around QPSK points reference carrier phase angle is corrected noise in non-carrier bins is suppressed resultant symbol is re-modulated removes pulse shaping function performs 2048 point FFT diminishing returns with each iteration computationally expensive

12 Proposed PAPR Reduction Standard PAPR reduction only considers the IBOC signal...what if we considered both the analog and digital signals together?

13 Proposed PAPR Reduction Standard PAPR reduction applied to hybrid FM+IBOC signal

14 Proposed PAPR Reduction Proposed PAPR reduction applied to hybrid FM+IBOC signal

15 HD Power Boost: additional clean power

16 Measured Data NV20 IBOC Injection Measured PAR (db) no boost Measured PAR (db) w/boost PAR Reduction Measured AC to RF Efficiency Efficiency Increase %

17 Coverage Reduction by increased MER Data Carrier MER Reduction in Service Contour 18 db.22 db 17 db.25 db 16 db.31 db 15 db.37 db 14 db.48 db 13 db.59 db 12 db.74 db 11 db.91 db 10 db 1.13 db 9 db 1.38 db 8 db 1.73 db ibiquity system specification is 14 db Nautel s most aggressive PAPR is 16.5, well exceeding the spec Typical system performance without Nautel PAPR is db Means a 20 kw transmitter can produce 15 kw of analog + HD (at -10 dbc) compared with ~11 kw without Nautel PAPR.

18 HD PowerBoost HD PowerBoost HD PowerBoost HD PowerBoost HD PowerBoost HD PowerBoost HD Power Boost: Efficiency

19 Nautel -10dB/-14dB Solutions HD PowerBoost Asymmetrical Sidebands NV Series High Power Solid State NAUTEL IS ONLY SINGLE BOX SOLUTION ABOVE dbc Later this year VS Digital

20 MIA-FLL-WPB MARKET HIGHLIGHTS -10 dbc (both SB) Asymmetrical -14 dbc (both SB) WHDR WDNA -14 / -10 WLDI WMIA WLRN -10 / -14 WMGE WLYF -13 / -10 WPOW WXEL -14 / -10 WFLC WKGR -14 / -10 WRTO -12 / -12 WEDR WKIS WMXJ WMIB WHQT WBBG WEAT WIRK

21 Asymmetrical Sidebands Not yet FCC approved Capability comes with HD PowerBoost Optimizes coverage to actual interference conditions. Individual sidebands adjustable in 1 db increments from -20 up to -10 dbc through AUI Can be used with or without PowerBoost

22 Factors That Can Improve De-rating Peak-to-Average Power Ratio Reduction (PAPR) such as Nautel s PowerBoost can yield an additional 30% in available analog -10 dbc Asymmetrical sideband technology optimizes power in upper and lower sidebands.

23 Demonstration PowerBoost and Differential Sideband Power

24 Factors That Can Degrade De-rating Tube vs. Solid State Tubes generally de-rate faster as injection approaches -10 dbc Extended hybrid modes Depending on the Mode (MP2, MP3, MP11,etc.), require additional de-ratings due to additional digital carriers MP3 mode ~6% at -10 dbc (2 extended partitions) MP11 mode ~13% at -10 dbc (4 extended partitions) (Note Mode not commercialized) Check with your transmitter manufacturer!!

25 Transmitters: Power Ratings

26 Antenna Options: More Gain Add bays to increase gain Increase injection without changing the transmitter power Increases system efficiency Considerations Space on tower (additional $ $ for rent?) Weight and wind load Impedance matching Coverage in antenna nulls Digital spectral purity tighter requirement

27 Transmitters: High Power Combined Higher injection means more power wasted in reject load % Power to Reject Load % dB -14dB Analog Digital -10dB

28 High Level Combining Modification Coupling Ratio Licensed TPO Total Analog Power Required Digital Power Total New Digital Power Boost in db Total Reject Power

29 Transmitters: Space Combined Considerations Tower and building space? analog vs. digital radiation pattern differences RF IMD issues: higher power filters required circulators may be required Verify digital antenna ratings: voltage and power New developments in digital-only transmitters (11kW digital from an NV20)

30 Transmitters: Higher Power Hybrid Simple architecture - simplest method Single box installation (unless paralleling) Higher HD injection level may reduce the analog TPO capability (see power chart) May need to replace your transmitter or combine another for higher total power Higher injection levels reduce efficiency* * Nautel s HD Power Boost can increase digital injection while increasing the efficiency of your existing NV transmitter.

31 Low Loss Combining Recent article in RW on this technology Down side: large size, weight, cost

32 Attention to Specifications Model # NV 3.75 NV 5 NV 7.5 NV 10 NV 15 NV 20 NV 30 NV 40 Comb 2,184 2,912 4,368 5,824 8,736 11,647 17,471 23, FM (TPO) 1,985 2,647 3,971 5,294 7,941 10,589 15,883 21,177 IBOC ,059 1,588 2,118 Keep in mind the relationship between combined total RMS power, and available analog FM TPO.

33 Summary: Digital Coverage HD injection level requirements range from -20dB to -10dB depending on noise environment/allocation Good news: A wide range of increased digital injection strategies exist Nautel has single box solid state transmitter solutions up to 44kW analog, 34kW at -14dB Buy for -20dB, get up to -14dB with HD PowerBoost HD PowerBoost may permit the purchase of a smaller transmitter size + increase efficiency Booth C2615 LIVE HD PowerBoost Demo

34 V Series Upgrade Path V Series with M50 can be upgraded to -14 Modification on PA boards cut out ferrite Use serial port and input some codes to adjust the injection level Customer service can provide you a power chart and full instructions Levels above -14 dbc unlikely Use spectrum analyzer to verify mask HD PowerBoost & differential sideband power presently not available on V Series

35 An Important Point to Ponder Each sideband s digital carriers were originally at -23 dbc, and added together = -20 dbc or 1% dbc 10,000 Watts dbc -23 dbc 50 Watts 50 Watts -41 f, khz Channel Center Frequency

36 An Important Point to Ponder At -10 dbc, we really are at -13 dbcdbcor added together, at -10 dbc or 10% of analog power O 10,000 Watts dbc -13 dbc -23 dbc 500 Watts Watts Watts -41 f, khz Channel Center Frequency

37 An Important Point to Ponder Example of station with -14 dbc lower and -10 dbc upper sideband power Total integrated power is dbc dbc or 7% of analog O 10,000 Watts dbc -13 dbc -23 dbc 200 Watts Watts Watts -41 f, khz Channel Center Frequency

38 Calculating the True Integrated (Total) Digital Power Convert to simple power ratio -13 dbc =.05 and -17 dbc =.02 Combined power = 10*log ( ) = dbc LSB 200 W + USB 500 W = 700 W 700/10,000 =.07 * 100 = 7% of analog power

39 Acknowledgements Putting the Quality Metric to the Test (Philipp Schmid, Nautel 2010) A New Approach to Peak-to-Average-Power Reduction for Hybrid FM+IBOC Transmission (Philipp Schmid, Nautel 2008)

40 Questions? We re ready to help. Gary Manteuffel Gary Liebisch Jeff Welton Ellis Terry John Bisset Gerardo Vargas John Abdnour Hal Kneller Wendell Lonergan Steve Schmitt Chuck Kelly US Corporate Accounts & Canada Eastern US Central US Western US Europe & Southern Africa Latin America / Caribbean Asia / Pacific Market Development Manager Middle East & Northern Africa Sales Engineer Director of Sales