Applications for Deployable Helical and Quadrifilar Helical Antennas for Small Satellites
Session
Technical Poster Session I
Location
Utah State University, Logan, UT
Abstract
Deployable Helical and Quadrifilar Helical Antennas put a larger footprint on earth than typical monopole or dipole antennas. Small satellites with limited available power need optimum use of their antenna radiating structure.
Practical experience over past years with Deployable Helical and Quadrifilar Helical has provided guidance for new small satellite applications. Realistic expectations for frequency bands on the various face sizes will be discussed.
Desired Beamwidth is tempered with the size of the small satellite. Isoflux antennas at frequencies below about 600 MHz will require a 2U by 2U face
This paper will discuss applications of the Helical and Quadrature Helical Antennas (QHA). QHAs used on the satellite as well as at the ground station can provide an easy to locate small satellite.
QHA simulations indicate the potential for improved small satellite communications A couple baseline QHAs will be described for 400 MHz, 860 to 930 MHz, L and S Band applications.
The QHA can generate an Iso-Flux antenna patterns. The Iso-Flux pattern puts emphasis on presenting higher antenna gain at low elevation angles where the communication range is significantly larger than simple monopoles could cover.
NiTinol shape memory wire has strain limits that has changed how we apply the NiTinol alloy wire. Superelastic NiTinol reduces the need for energy required to deploy the antenna.
One of the reasons QHAs are not prevalent on small satellites has to do with their complicated structure and need to remain dimensionally true when deployed. Small antenna modules can be developed with a means to deploy the QHA structure after launch. There are several tasks to accomplish in order to transform an unbalanced transmission line to four quadrature sources providing 0, 90, 180, and 270 degree power split sources. This paper will discuss various methods to accomplish the feed mechanism for Quadrifilar Helical Antennas.
Recent advances in Quadrifilar Helical Antenna development for small satellites now allow the antenna to be stowed in a module consistent with 1U modules. The purpose of this paper will be to show the potential results of using the Quadrifilar Helical Antenna to provide better communications for small satellites. Antenna patterns along with bandwidth coverage will be presented.
The concepts presented are providing significant advances in small satellite communications.
Disadvantages of Monopole Antennas:
Many small satellites use simple monopole antennas for their communication to and from terrestrial ground stations. The monopole antenna patterns are mostly linearly polarized. The monopole antenna is dependent on the rest of the small satellite for the ground or counterpoise. The ground stations may use a more capable antenna, either a Yagi with higher gain or a circularly polarized antenna with high gain. The ground station may need to use Azimuth-Elevation dual rotator techniques to point the antenna toward the small satellite as well as a computer program to automatically direct the antenna toward the small satellite. It is even more difficult to locate recently launched small satellites without well-defined orbits.
Applications for Deployable Helical and Quadrifilar Helical Antennas for Small Satellites
Utah State University, Logan, UT
Deployable Helical and Quadrifilar Helical Antennas put a larger footprint on earth than typical monopole or dipole antennas. Small satellites with limited available power need optimum use of their antenna radiating structure.
Practical experience over past years with Deployable Helical and Quadrifilar Helical has provided guidance for new small satellite applications. Realistic expectations for frequency bands on the various face sizes will be discussed.
Desired Beamwidth is tempered with the size of the small satellite. Isoflux antennas at frequencies below about 600 MHz will require a 2U by 2U face
This paper will discuss applications of the Helical and Quadrature Helical Antennas (QHA). QHAs used on the satellite as well as at the ground station can provide an easy to locate small satellite.
QHA simulations indicate the potential for improved small satellite communications A couple baseline QHAs will be described for 400 MHz, 860 to 930 MHz, L and S Band applications.
The QHA can generate an Iso-Flux antenna patterns. The Iso-Flux pattern puts emphasis on presenting higher antenna gain at low elevation angles where the communication range is significantly larger than simple monopoles could cover.
NiTinol shape memory wire has strain limits that has changed how we apply the NiTinol alloy wire. Superelastic NiTinol reduces the need for energy required to deploy the antenna.
One of the reasons QHAs are not prevalent on small satellites has to do with their complicated structure and need to remain dimensionally true when deployed. Small antenna modules can be developed with a means to deploy the QHA structure after launch. There are several tasks to accomplish in order to transform an unbalanced transmission line to four quadrature sources providing 0, 90, 180, and 270 degree power split sources. This paper will discuss various methods to accomplish the feed mechanism for Quadrifilar Helical Antennas.
Recent advances in Quadrifilar Helical Antenna development for small satellites now allow the antenna to be stowed in a module consistent with 1U modules. The purpose of this paper will be to show the potential results of using the Quadrifilar Helical Antenna to provide better communications for small satellites. Antenna patterns along with bandwidth coverage will be presented.
The concepts presented are providing significant advances in small satellite communications.
Disadvantages of Monopole Antennas:
Many small satellites use simple monopole antennas for their communication to and from terrestrial ground stations. The monopole antenna patterns are mostly linearly polarized. The monopole antenna is dependent on the rest of the small satellite for the ground or counterpoise. The ground stations may use a more capable antenna, either a Yagi with higher gain or a circularly polarized antenna with high gain. The ground station may need to use Azimuth-Elevation dual rotator techniques to point the antenna toward the small satellite as well as a computer program to automatically direct the antenna toward the small satellite. It is even more difficult to locate recently launched small satellites without well-defined orbits.
