A third type of printed dipole
MPAR (Multi purpose Phased Array Radar) antenna that can be considered intermediate type of the two shown above. This one is for much higher frequencies and thus smaller. But has the printed dipole flange concept, just crossed.
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I was asked to comment on Space-x last Ex parte letter that they have filed to the FCC.
So here is the picture:
$ASTS has asked authority to launch full constellation beyond 25 satellites.
Space-x wants to delay and complicate that.
They keep filing all the way to sunshine 1/
It’s extremely uncompetitive behaviour and a bit immoral as what Space-X has begged be implemented onto AST is the same type of regulations they see as an obstacle when applied to themselves.
What they ask that AST shall not be allowed to is what they themselves do.
Golden rule?
It’s important to grasp that the next 20 satellites and the Block1s are approved already.
So this pen-fighting is about about satellites to launched beyond Q1 2026.
_One way to increase Area spectral efficiency is lowering constellation altitude.
That way comes at two costs: The number of 🛰️satellites required on orbit increases and their orbital dwell ⏳time decreases both affecting the replenish rate 🛠️adversely as:
🛠️ = 🛰️/⏳
🧶🐈⬛
1/n
Let’s do a SpaceMob thing and look at this from first principles.
A satellite has a field of view. FoV.
That Field of View projects a footprint on earth.
The footprint increases with angle of the field of view and increases with altitude.
2/
Within this field of view the satellite creates beams.
They also have an angle called beamwidth and a footprint called beamcell.
There are many of these beams and beamcells within the satellite footprint.
🚨 $ASTS IS INCREASING ITS PATENT MOAT ESP. ON DOW ORBITS 🚨THIS PATENT COVERS THE SIGNAL-PROCESSING METHODS — SELECTION COMBINING, DIVERSITY COMBINING, AND MIMO — THAT ENABLE RELIABLE DIRECT-TO-CELL CONNECTIVITY FROM LEO SATELLITES TO STANDARD HANDSETS.
1/
THE PROBLEM ADDRESSED: END USER DEVICES MAY RECEIVE MULTIPLE SATELLITE SIGNALS (MULTIPLE PATHS, SUB-ARRAYS, OR MULTI-SATELLITE LINKS) WITH DIFFERENT DELAYS, DOPPLER, AND SNRS.
THE PATENT SPECIFIES HOW TO CHOOSE AND COMBINE THESE SIGNALS TO MAXIMIZE LINK RELIABILITY.
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SELECTION COMBINING: the system monitors multiple receive branches and selects the best branch using quality metrics (e.g., SNR/BER estimates, channel quality indicators). selection lowers complexity and power for the handset when one branch dominates