Posthumous Numerical Study of DTV Broadcast Antenna Integration with Prototype Stratospheric Airship Gondola

As a follow-on to the 2002 digital television (DTV) broadcast demonstration from a solar-powered stratospheric flying wing, a prototype stratospheric airship was used for a more realistic DTV broadcast demonstration in 2004, albeit at a lower altitude. The DTV signal was occasionally lost at the receiver directly below the airship during the demonstration. Adverse antenna-vehicle integration effects were investigated using a commercially available antenna simulation software, because the radiation pattern of the antenna on the airship could not be measured directly. The ground handling bars on the airship gondola were found to introduce deep and sharp nulls into the radiation pattern of the broadcast antenna. Some mitigation techniques that would have fitted within the constraints of the time are discussed. Changing to nonconductive ground handling bars and a multiturn helical antenna would have avoided the problem, according to the simulation results.

[1]  A. Kumar.  Microstrip antennas guide satellite data transmissions , 2005 .

[2]  Paul E. Mayes,et al.  New circular-polarized frequency-independent antennas with conical beam or omnidirectional patterns , 1961 .

[3]  R. Miura,et al.  Review of helices for DTV broadcast from HAPS prototype , 2006, 2006 Asia-Pacific Microwave Conference.

[4]  H. Aubert,et al.  Compact printed quadrifilar helix antennas for stratospheric balloons telemetry , 2007, 2007 IEEE Antennas and Propagation Society International Symposium.

[5]  Y. Yokomaku,et al.  Overview of stratospheric platform airship R&D program in Japan , 2000 .

[6]  J. Kraus,et al.  The Helical Antenna , 1949, Proceedings of the IRE.

[7]  P. Besnier,et al.  A size reduced configurations of printed quadrifilar helix antenna , 2005, IWAT 2005. IEEE International Workshop on Antenna Technology: Small Antennas and Novel Metamaterials, 2005..

[8]  Fotini-Niovi Pavlidou,et al.  Broadband communications via high-altitude platforms: a survey , 2005, IEEE Communications Surveys & Tutorials.

[9]  Mikio Suzuki,et al.  Testing of digital television broadcasting from the stratosphere , 2004, IEEE Transactions on Broadcasting.

[10]  M. Onda,et al.  A stratospheric LTA stationary platform for telecommunication and environmental protection , 1999, SICE '99. Proceedings of the 38th SICE Annual Conference. International Session Papers (IEEE Cat. No.99TH8456).

[11]  J. Huang,et al.  Circularly polarized conical patterns from circular microstrip antennas , 1984 .

[12]  Surjit Badesha,et al.  Very high altitude tethered balloon parametric sensitivity study , 1996 .

[13]  S. Saunders,et al.  Meander line technique for size reduction of quadrifilar helix antenna , 2002, IEEE Antennas and Wireless Propagation Letters.

[14]  C. Kilgus,et al.  Shaped-conical radiation pattern performance of the backfire quadrifilar helix , 1975 .

[15]  R. Cahill,et al.  Performance of shaped beam quadrifilar antennas on the METOP spacecraft , 1998 .

[16]  R. Miura,et al.  Autopsy of unmanned airship television broadcast , 2006, 2006 IEEE Antennas and Propagation Society International Symposium.

[17]  Alan Victor.  Airship/U.S. naval vessels UHF communications relay demonstration , 1993 .

[18]  Hiroyuki Tsuji,et al.  Experiments on IMT-2000 using unmanned solar powered aircraft at an altitude of 20 km , 2005, IEEE Transactions on Vehicular Technology.