Attachment Spec Report

This document pretains to SAT-LOI-20180910-00069 for Letter of Intent on a Satellite Space Stations filing.

IBFS_SATLOI2018091000069_1526603

FEASIBILITY REPORT ON VARIOUS 400 MHZ RHCP ANTENNA CONFIGURATIONS July 24, 2017 Specification Report on 400 MHz Antenna Contents 1 Specification ....................................................................................................................... 3 2 Single QHA directed at the Nadir ........................................................................................ 3 Geometry of a single QHA ........................................................................................... 3 3D View of the Right Hand Circular Antenna Pattern ................................................... 4 3D antenna pattern along X and Y axis ........................................................................ 4 2D Polar View, showing Max RHCP Gain is >4.6 dBirhcp ............................................ 5 Rectangular view showing -3 dBi Beamwidth of 120Deg.............................................. 5 Gain vs Frequency shows 4.6 dBiRHCP gain at 400 MHz ........................................... 6 Smith Chart .................................................................................................................. 6 3 Single QHA Recessed 30 mm into 6U Cube Sat ................................................................. 7 Geometry of 30mm Recessed QHA ............................................................................. 7 3D View of the Right Hand Circular Antenna Pattern ................................................... 8 3D ant pattern along X axis, in YZ plane ...................................................................... 9 3D ant pattern in YZ plane ........................................................................................... 9 2D Polar Elevation View, Y axis, in XZ plane ..............................................................10 Rectangular view showing -3 dBi Beamwidth of 107 Deg............................................10 Gain vs Frequency showing 4.6 dBiRHCP gain at 400 MHz .......................................11 Smith Chart .................................................................................................................12 4 2nd Harmonic Response for Single QHA Recessed 30 mm into 6U Cube Sat ....................13 5 3rd Harmonic Response for Single QHA Recessed 30 mm into 6U Cube Sat ....................14 Helical Communication Technologies July 30, 2017 Page 1 of 14

FEASIBILITY REPORT ON VARIOUS 400 MHZ RHCP ANTENNA CONFIGURATIONS The antenna presented herein are feasible to construct. These are deployable antennas. The antenna bifilar loops are constructed using NiTinol wire. These bifilar loops are situated on a printed wiring board. The capacitor and inductor components are realizable; that is, they are of practical values. The NiTinol construction allows the antenna to be stowed within the cube sat structure. After launching into Low Earth Orbit, the antenna may be deployed by applying an electrical direct current. HCT advocates use of a High Efficiency Voltage Regulator with Current Limiting circuit placed on the underside of the antenna PCB. Recent measurements recommend a current limiting circuit at about 4 amperes. The Voltage floats from about 3 to 5 volts. The power is applied for about 60 seconds. The antenna deployment benefits from solar heating in Low Earth Orbit. We look forward to working with Magnitude Space to develop a Quadrifilar Helical Antenna suited to your desired specifications. Gregory O’Neill, Chairman Helical Communication Technologies 634 Barnes Blvd Rockledge, FL 32955 (321.208.8978) greg@HCTemail.com http://HeliComTech.com Helical Communication Technologies July 30, 2017 Page 2 of 14

FEASIBILITY REPORT ON VARIOUS 400 MHZ RHCP ANTENNA CONFIGURATIONS 1 Specification This report presents a Specification Report for a Single Quadrifilar Helical Antenna. The Feasibility Study results have shown that a single Quadrifilar Helical Antenna really is the practical way to proceed. It offers a nearly uniform X axis and Y axis footprint on earth below the satellite. The report establishes performance of a Single QHA on a 100x100mm ground plane as a baseline. For the graphs that follow, +X is pictured as the forward direction of the spacecraft and -Z is the nadir. It is important to be aware of the orientation of the antenna and 3D views. The orthogonal views of the antenna pattern and gain vs frequency graphs are plotted with respect to origin. The rectangular view shows the beamwidth in the nadir. Gain directed at the nadir: Greater than +4 dBiRHCP Beamwidth mounted on 6U ISIS Cube Sat structure: Between 110 and 120 Degrees 2 Single QHA directed at the Nadir Geometry of a single QHA Helical Communication Technologies July 30, 2017 Page 3 of 14

FEASIBILITY REPORT ON VARIOUS 400 MHZ RHCP ANTENNA CONFIGURATIONS Axial Ht = 286 mm Prox Dia = 75 mm Dist Dia 35.5 mm Pitch.Angle = 58 Deg Cseries = 15 pF Lshunt = 8 nH Lmatch = 62 nH Cbalun = 6.6 pF Lbalun = 18.5 nH The single QHA by itself is an appropriate reference antenna 3D View of the Right Hand Circular Antenna Pattern Maximum RHCP Gain = 4.6 dBirhcp, Orthographic View 3D antenna pattern along X and Y axis Maximum RH Gain = 4.61 dBi These graphs show symmetrical X and Y axis performance. Helical Communication Technologies July 30, 2017 Page 4 of 14

FEASIBILITY REPORT ON VARIOUS 400 MHZ RHCP ANTENNA CONFIGURATIONS 2D Polar View, showing Max RHCP Gain is >4.6 dBirhcp This view is in the Y axis, in the XZ plane. The background is scaled in 2 dBi increments. Rectangular view showing -3 dBi Beamwidth of 120Deg This view is in the Y axis, in the XZ plane. The background is scaled in 2 dBi increments. Helical Communication Technologies July 30, 2017 Page 5 of 14

FEASIBILITY REPORT ON VARIOUS 400 MHZ RHCP ANTENNA CONFIGURATIONS Gain vs Frequency shows 4.6 dBiRHCP gain at 400 MHz SMITH CHART The antenna is matched well over the 5 MHz bandwidth centered on 400 MHz. Helical Communication Technologies July 30, 2017 Page 6 of 14

FEASIBILITY REPORT ON VARIOUS 400 MHZ RHCP ANTENNA CONFIGURATIONS 3 Single QHA Recessed 30 mm into 6U Cube Sat Geometry of 30mm Recessed QHA The recessed distance of the antenna into the structure affects the antenna pattern. This case uses a 100x100x10 Grid, representing the Printed Circuit Board the antenna is mounted on. Axial Ht = 293 mm Prox Dia = 75 mm Dist Dia 35.5 mm Pitch.Angle = 56 Deg Cseries = 270 pF Lseries = 4 nH Lshunt = 50 nH Cbalun = 7.7 pF Lbalun = 4.6 nH HCT is in the process of changing to use the High Frequency Structure Simulator. The main improvement is likely to be in the printed circuit board impedances. Therefore, the capacitor and inductor values are likely to change. Helical Communication Technologies July 30, 2017 Page 7 of 14

FEASIBILITY REPORT ON VARIOUS 400 MHZ RHCP ANTENNA CONFIGURATIONS 3D View of the Right Hand Circular Antenna Pattern Maximum RHCP Gain is 4.6 dBi Orthographic View. The antenna recess mounted in the Cube Sat structure 30 mm indicates 0.2 dB decrease over the antenna by itself. Helical Communication Technologies July 30, 2017 Page 8 of 14

FEASIBILITY REPORT ON VARIOUS 400 MHZ RHCP ANTENNA CONFIGURATIONS 3D ant pattern along X axis, in YZ plane Maximum RH Gain = 4.6 dBi 3D ant pattern in YZ plane Maximum RH Gain = 4.6 dBi Note: The XZ and YZ plane views are nearly identical indicating a very symmetrical pattern. Helical Communication Technologies July 30, 2017 Page 9 of 14

FEASIBILITY REPORT ON VARIOUS 400 MHZ RHCP ANTENNA CONFIGURATIONS 2D Polar Elevation View, Y axis, in XZ plane Maximum RH Gain = 4.6 dBi Rectangular view showing -3 dBi Beamwidth of 107 Deg The beamwidth is slightly affected by the cube sat structure. The beamwidth may vary when the actual antenna is built and placed on the satellite with the solar panels. Helical Communication Technologies July 30, 2017 Page 10 of 14

FEASIBILITY REPORT ON VARIOUS 400 MHZ RHCP ANTENNA CONFIGURATIONS Gain vs Frequency showing 4.6 dBiRHCP gain at 400 MHz The gain vs frequency varies 1.1 dB over the 5 MHz band. The satellite structure and the solar panels affect the antenna pattern and impedance match. After considerable simulation HCT has determined it will be best to operate the antenna significantly off maximum gain. This allows the antenna to perform with minimum affects to the performance compared to an antenna without the satellite structure and the solar panels. Helical Communication Technologies July 30, 2017 Page 11 of 14

FEASIBILITY REPORT ON VARIOUS 400 MHZ RHCP ANTENNA CONFIGURATIONS Smith Chart The antenna driving point impedance shows a very good SWR. Helical Communication Technologies July 30, 2017 Page 12 of 14

FEASIBILITY REPORT ON VARIOUS 400 MHZ RHCP ANTENNA CONFIGURATIONS 4 2ND HARMONIC RESPONSE FOR SINGLE QHA RECESSED 30 MM INTO 6U CUBE SAT Helical Communication Technologies July 30, 2017 Page 13 of 14

FEASIBILITY REPORT ON VARIOUS 400 MHZ RHCP ANTENNA CONFIGURATIONS 5 3RD HARMONIC RESPONSE FOR SINGLE QHA RECESSED 30 MM INTO 6U CUBE SAT Helical Communication Technologies July 30, 2017 Page 14 of 14


Document Created: 2017-07-30 12:27:58
Document Modified: 2017-07-30 12:27:58
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