IEEE - Aerospace and Electronic Systems - September 2019 - 57

him to conduct experiments with electromagnetic radiation. He then worked for the Siemens and Schuckert company in Bremen, supervising electrical installations in
battlecruisers, but left this employment in April 1902 and
moved to D€usseldorf where he continued his experimental
scientific work. He was able to obtain financial support
from a leather merchant in K€oln (Cologne).
At one point in his earlier life, he had seen his
mother comforting a woman whose son had been
drowned when two vessels collided in foggy conditions
on the Weser river, and this clearly made a big impression on him. He conceived the idea of a device that
could detect the presence of a distant obstacle, even in
conditions of poor visibility, by means of reflected electromagnetic radiation. He filed a patent on 21 November
1903 for what he called a Telemobiloskop, but it was
rejected, either because his claims infringed existing patents or because they were not considered to constitute a
genuine invention. But by early 1904, his invention had
developed to the point where he was confident enough
to demonstrate it to the public. On 17 May 1904 he had
arranged a public demonstration at the Dom Hotel in
K€oln, and later the same day the apparatus was taken to
the banks of the Rhine river, next to the Hohenzollern
Bridge, to demonstrate the detection of a barge at a
range of several hundred meters. Figure 2 shows a

Figure 1.
Example of an IEEE milestone plaque-in this case marking the
invention of the diode valve in 1904 by John Ambrose Fleming at
University College London.

SEPTEMBER 2019

picture of H€
ulsmeyer. It is worth appreciating that he
was just 22 years old at the time of his invention.
The demonstrations were reported in the K€
olner Tageblatt and K€
olnischer Zeitung newspapers the next day.
These are printed in the Sutterlin Gothic script of the time
(Figure 3). Translations of some sentences from these
reports read as follows:
After the transmitter had been activated, and the
waves returned to the receiver after reflection
at the gate door, the receiver switched on a light
bulb which also initiated the activation of a
small motor-mechanism. This motor mechanism

Figure 2.
Christian H€ulsmeyer, just a few years after the time that he
devised and patented his invention.

IEEE A&E SYSTEMS MAGAZINE

57



IEEE - Aerospace and Electronic Systems - September 2019

Table of Contents for the Digital Edition of IEEE - Aerospace and Electronic Systems - September 2019

Contents
IEEE - Aerospace and Electronic Systems - September 2019 - Cover1
IEEE - Aerospace and Electronic Systems - September 2019 - Cover2
IEEE - Aerospace and Electronic Systems - September 2019 - Contents
IEEE - Aerospace and Electronic Systems - September 2019 - 2
IEEE - Aerospace and Electronic Systems - September 2019 - 3
IEEE - Aerospace and Electronic Systems - September 2019 - 4
IEEE - Aerospace and Electronic Systems - September 2019 - 5
IEEE - Aerospace and Electronic Systems - September 2019 - 6
IEEE - Aerospace and Electronic Systems - September 2019 - 7
IEEE - Aerospace and Electronic Systems - September 2019 - 8
IEEE - Aerospace and Electronic Systems - September 2019 - 9
IEEE - Aerospace and Electronic Systems - September 2019 - 10
IEEE - Aerospace and Electronic Systems - September 2019 - 11
IEEE - Aerospace and Electronic Systems - September 2019 - 12
IEEE - Aerospace and Electronic Systems - September 2019 - 13
IEEE - Aerospace and Electronic Systems - September 2019 - 14
IEEE - Aerospace and Electronic Systems - September 2019 - 15
IEEE - Aerospace and Electronic Systems - September 2019 - 16
IEEE - Aerospace and Electronic Systems - September 2019 - 17
IEEE - Aerospace and Electronic Systems - September 2019 - 18
IEEE - Aerospace and Electronic Systems - September 2019 - 19
IEEE - Aerospace and Electronic Systems - September 2019 - 20
IEEE - Aerospace and Electronic Systems - September 2019 - 21
IEEE - Aerospace and Electronic Systems - September 2019 - 22
IEEE - Aerospace and Electronic Systems - September 2019 - 23
IEEE - Aerospace and Electronic Systems - September 2019 - 24
IEEE - Aerospace and Electronic Systems - September 2019 - 25
IEEE - Aerospace and Electronic Systems - September 2019 - 26
IEEE - Aerospace and Electronic Systems - September 2019 - 27
IEEE - Aerospace and Electronic Systems - September 2019 - 28
IEEE - Aerospace and Electronic Systems - September 2019 - 29
IEEE - Aerospace and Electronic Systems - September 2019 - 30
IEEE - Aerospace and Electronic Systems - September 2019 - 31
IEEE - Aerospace and Electronic Systems - September 2019 - 32
IEEE - Aerospace and Electronic Systems - September 2019 - 33
IEEE - Aerospace and Electronic Systems - September 2019 - 34
IEEE - Aerospace and Electronic Systems - September 2019 - 35
IEEE - Aerospace and Electronic Systems - September 2019 - 36
IEEE - Aerospace and Electronic Systems - September 2019 - 37
IEEE - Aerospace and Electronic Systems - September 2019 - 38
IEEE - Aerospace and Electronic Systems - September 2019 - 39
IEEE - Aerospace and Electronic Systems - September 2019 - 40
IEEE - Aerospace and Electronic Systems - September 2019 - 41
IEEE - Aerospace and Electronic Systems - September 2019 - 42
IEEE - Aerospace and Electronic Systems - September 2019 - 43
IEEE - Aerospace and Electronic Systems - September 2019 - 44
IEEE - Aerospace and Electronic Systems - September 2019 - 45
IEEE - Aerospace and Electronic Systems - September 2019 - 46
IEEE - Aerospace and Electronic Systems - September 2019 - 47
IEEE - Aerospace and Electronic Systems - September 2019 - 48
IEEE - Aerospace and Electronic Systems - September 2019 - 49
IEEE - Aerospace and Electronic Systems - September 2019 - 50
IEEE - Aerospace and Electronic Systems - September 2019 - 51
IEEE - Aerospace and Electronic Systems - September 2019 - 52
IEEE - Aerospace and Electronic Systems - September 2019 - 53
IEEE - Aerospace and Electronic Systems - September 2019 - 54
IEEE - Aerospace and Electronic Systems - September 2019 - 55
IEEE - Aerospace and Electronic Systems - September 2019 - 56
IEEE - Aerospace and Electronic Systems - September 2019 - 57
IEEE - Aerospace and Electronic Systems - September 2019 - 58
IEEE - Aerospace and Electronic Systems - September 2019 - 59
IEEE - Aerospace and Electronic Systems - September 2019 - 60
IEEE - Aerospace and Electronic Systems - September 2019 - 61
IEEE - Aerospace and Electronic Systems - September 2019 - 62
IEEE - Aerospace and Electronic Systems - September 2019 - 63
IEEE - Aerospace and Electronic Systems - September 2019 - 64
IEEE - Aerospace and Electronic Systems - September 2019 - Cover3
IEEE - Aerospace and Electronic Systems - September 2019 - Cover4
https://www.nxtbook.com/nxtbooks/ieee/aerospace_december2023
https://www.nxtbook.com/nxtbooks/ieee/aerospace_november2023
https://www.nxtbook.com/nxtbooks/ieee/aerospace_october2023
https://www.nxtbook.com/nxtbooks/ieee/aerospace_september2023
https://www.nxtbook.com/nxtbooks/ieee/aerospace_august2023
https://www.nxtbook.com/nxtbooks/ieee/aerospace_july2023
https://www.nxtbook.com/nxtbooks/ieee/aerospace_june2023
https://www.nxtbook.com/nxtbooks/ieee/aerospace_may2023
https://www.nxtbook.com/nxtbooks/ieee/aerospace_april2023
https://www.nxtbook.com/nxtbooks/ieee/aerospace_march2023
https://www.nxtbook.com/nxtbooks/ieee/aerospace_february2023
https://www.nxtbook.com/nxtbooks/ieee/aerospace_january2023
https://www.nxtbook.com/nxtbooks/ieee/aerospace_december2022
https://www.nxtbook.com/nxtbooks/ieee/aerospace_november2022
https://www.nxtbook.com/nxtbooks/ieee/aerospace_october2022
https://www.nxtbook.com/nxtbooks/ieee/aerospace_september2022
https://www.nxtbook.com/nxtbooks/ieee/aerospace_august2022
https://www.nxtbook.com/nxtbooks/ieee/aerospace_july2022
https://www.nxtbook.com/nxtbooks/ieee/aerospace_june2022
https://www.nxtbook.com/nxtbooks/ieee/aerospace_may2022_tutorial
https://www.nxtbook.com/nxtbooks/ieee/aerospace_may2022
https://www.nxtbook.com/nxtbooks/ieee/aerospace_april2022
https://www.nxtbook.com/nxtbooks/ieee/aerospace_march2022
https://www.nxtbook.com/nxtbooks/ieee/aerospace_february2022
https://www.nxtbook.com/nxtbooks/ieee/aerospace_january2022
https://www.nxtbook.com/nxtbooks/ieee/aerospace_december2021
https://www.nxtbook.com/nxtbooks/ieee/aerospace_november2021
https://www.nxtbook.com/nxtbooks/ieee/aerospace_october2021
https://www.nxtbook.com/nxtbooks/ieee/aerospace_september2021
https://www.nxtbook.com/nxtbooks/ieee/aerospace_august2021
https://www.nxtbook.com/nxtbooks/ieee/aerospace_july2021
https://www.nxtbook.com/nxtbooks/ieee/aerospace_june2021
https://www.nxtbook.com/nxtbooks/ieee/aerospace_may2021
https://www.nxtbook.com/nxtbooks/ieee/aerospace_april2021
https://www.nxtbook.com/nxtbooks/ieee/aerospace_march2021
https://www.nxtbook.com/nxtbooks/ieee/aerospace_march2021_tutorials
https://www.nxtbook.com/nxtbooks/ieee/aerospace_february2021
https://www.nxtbook.com/nxtbooks/ieee/aerospace_january2021
https://www.nxtbook.com/nxtbooks/ieee/aerospace_november2020
https://www.nxtbook.com/nxtbooks/ieee/aerospace_december2020
https://www.nxtbook.com/nxtbooks/ieee/aerospace_october2020
https://www.nxtbook.com/nxtbooks/ieee/aerospace_september2020
https://www.nxtbook.com/nxtbooks/ieee/aerospace_august2020
https://www.nxtbook.com/nxtbooks/ieee/aerospace_july2020
https://www.nxtbook.com/nxtbooks/ieee/aerospace_june2020
https://www.nxtbook.com/nxtbooks/ieee/aerospace_may2020
https://www.nxtbook.com/nxtbooks/ieee/aerospace_april2020
https://www.nxtbook.com/nxtbooks/ieee/aerospace_march2020
https://www.nxtbook.com/nxtbooks/ieee/aerospace_february2020
https://www.nxtbook.com/nxtbooks/ieee/aerospace_january2020
https://www.nxtbook.com/nxtbooks/ieee/aerospace_december2019
https://www.nxtbook.com/nxtbooks/ieee/aerospace_october2019partII
https://www.nxtbook.com/nxtbooks/ieee/aerospace_november2019
https://www.nxtbook.com/nxtbooks/ieee/aerospace_october2019
https://www.nxtbook.com/nxtbooks/ieee/aerospace_july2019
https://www.nxtbook.com/nxtbooks/ieee/aerospace_september2019
https://www.nxtbook.com/nxtbooks/ieee/aerospace_august2019
https://www.nxtbook.com/nxtbooks/ieee/aerospace_june2019
https://www.nxtbook.com/nxtbooks/ieee/aerospace_april2019
https://www.nxtbook.com/nxtbooks/ieee/aerospace_may2019
https://www.nxtbook.com/nxtbooks/ieee/aerospace_march2019
https://www.nxtbook.com/nxtbooks/ieee/aerospace_december2018
https://www.nxtbook.com/nxtbooks/ieee/aerospace_august2018
https://www.nxtbook.com/nxtbooks/ieee/aerospace_october2018
https://www.nxtbook.com/nxtbooks/ieee/aerospace_september2018
https://www.nxtbook.com/nxtbooks/ieee/aerospace_november2018
https://www.nxtbookmedia.com