Aerospace and Electronic Systems Magazine March 2018 - 33

The baseline between the receiver and the transmitter is usually
beyond 1,000 km.
An experimental HFSSWR system was constructed by HIT
for academic research. The main components of this system are
the transmitting and receiving antenna arrays, the multichannel receiver system, the signal processing unit, the control and display
system, and the global positioning system (GPS) synchronization
facility. A block diagram of the system is shown in Figure 2.
The transmitting array consists of 10 elements, where each element is a log-periodic array of vertical monopoles. The bearing of
the transmit array is 70° clockwise from true north, the horizontal
beamwidth is 20°, and the vertical beamwidth is 45°. The power of
the transmitter is 3 kW. The bistatic configuration allows the transmitter to employ the 100%-duty frequency modulated continuous
wave (FMCW) waveform, which can maximize the average power.
The receiving system is based on a two-dimensional dual parallel uniform linear array located on the coastline in Weihai, Shandong Province. The array broadside is oriented 85° clockwise from
true north. A plan view of the antenna element layout and orienta-

tion is shown in Figure 3. Specifically, each subarray is composed
of 16 2-m-high active vertical monopole elements spaced 10-m
apart, yielding 32 receiving channels. The space between the subarrays is also 10 m. Each element has a matching unit mounted at
its base. The analog signals from the array are transmitted to a high
dynamic-range digital receiver by cable. The signals reflected by
the ionosphere and impinged on the receiving array directly are
so-called direct-wave signals. These signals are usually stronger
than target echoes. The receiver allows both signals to be received
simultaneously without saturating the analog-to-digital converter.

OBLIQUE INCIDENCE SOUNDER
To assist with data interpretation, an oblique incidence sounder
(OIS) is used to monitor the ionosphere. The sounder, which is a
"miniradar" system, sends a group of swept-frequency test signals
every 20 min. The carrier frequency is from 4 to 24 MHz, the carrier frequency interval is 100 kHz, the sweep bandwidth is 40 kHz,
and the sweep interval is 20 ms. In the OIS receiver, each sweep is

Figure 3.

Figure 2.

Plan view of the layout of elements in
the array and the orientation.

Transmitting and receiving system architecture.

MARCH 2018

IEEE A&E SYSTEMS MAGAZINE

33



Table of Contents for the Digital Edition of Aerospace and Electronic Systems Magazine March 2018

No label
Aerospace and Electronic Systems Magazine March 2018 - No label
Aerospace and Electronic Systems Magazine March 2018 - Cover2
Aerospace and Electronic Systems Magazine March 2018 - 1
Aerospace and Electronic Systems Magazine March 2018 - 2
Aerospace and Electronic Systems Magazine March 2018 - 3
Aerospace and Electronic Systems Magazine March 2018 - 4
Aerospace and Electronic Systems Magazine March 2018 - 5
Aerospace and Electronic Systems Magazine March 2018 - 6
Aerospace and Electronic Systems Magazine March 2018 - 7
Aerospace and Electronic Systems Magazine March 2018 - 8
Aerospace and Electronic Systems Magazine March 2018 - 9
Aerospace and Electronic Systems Magazine March 2018 - 10
Aerospace and Electronic Systems Magazine March 2018 - 11
Aerospace and Electronic Systems Magazine March 2018 - 12
Aerospace and Electronic Systems Magazine March 2018 - 13
Aerospace and Electronic Systems Magazine March 2018 - 14
Aerospace and Electronic Systems Magazine March 2018 - 15
Aerospace and Electronic Systems Magazine March 2018 - 16
Aerospace and Electronic Systems Magazine March 2018 - 17
Aerospace and Electronic Systems Magazine March 2018 - 18
Aerospace and Electronic Systems Magazine March 2018 - 19
Aerospace and Electronic Systems Magazine March 2018 - 20
Aerospace and Electronic Systems Magazine March 2018 - 21
Aerospace and Electronic Systems Magazine March 2018 - 22
Aerospace and Electronic Systems Magazine March 2018 - 23
Aerospace and Electronic Systems Magazine March 2018 - 24
Aerospace and Electronic Systems Magazine March 2018 - 25
Aerospace and Electronic Systems Magazine March 2018 - 26
Aerospace and Electronic Systems Magazine March 2018 - 27
Aerospace and Electronic Systems Magazine March 2018 - 28
Aerospace and Electronic Systems Magazine March 2018 - 29
Aerospace and Electronic Systems Magazine March 2018 - 30
Aerospace and Electronic Systems Magazine March 2018 - 31
Aerospace and Electronic Systems Magazine March 2018 - 32
Aerospace and Electronic Systems Magazine March 2018 - 33
Aerospace and Electronic Systems Magazine March 2018 - 34
Aerospace and Electronic Systems Magazine March 2018 - 35
Aerospace and Electronic Systems Magazine March 2018 - 36
Aerospace and Electronic Systems Magazine March 2018 - 37
Aerospace and Electronic Systems Magazine March 2018 - 38
Aerospace and Electronic Systems Magazine March 2018 - 39
Aerospace and Electronic Systems Magazine March 2018 - 40
Aerospace and Electronic Systems Magazine March 2018 - 41
Aerospace and Electronic Systems Magazine March 2018 - 42
Aerospace and Electronic Systems Magazine March 2018 - 43
Aerospace and Electronic Systems Magazine March 2018 - 44
Aerospace and Electronic Systems Magazine March 2018 - 45
Aerospace and Electronic Systems Magazine March 2018 - 46
Aerospace and Electronic Systems Magazine March 2018 - 47
Aerospace and Electronic Systems Magazine March 2018 - 48
Aerospace and Electronic Systems Magazine March 2018 - 49
Aerospace and Electronic Systems Magazine March 2018 - 50
Aerospace and Electronic Systems Magazine March 2018 - 51
Aerospace and Electronic Systems Magazine March 2018 - 52
Aerospace and Electronic Systems Magazine March 2018 - 53
Aerospace and Electronic Systems Magazine March 2018 - 54
Aerospace and Electronic Systems Magazine March 2018 - 55
Aerospace and Electronic Systems Magazine March 2018 - 56
Aerospace and Electronic Systems Magazine March 2018 - 57
Aerospace and Electronic Systems Magazine March 2018 - 58
Aerospace and Electronic Systems Magazine March 2018 - 59
Aerospace and Electronic Systems Magazine March 2018 - 60
Aerospace and Electronic Systems Magazine March 2018 - Cover3
Aerospace and Electronic Systems Magazine March 2018 - Cover4
http://www.brightcopy.net/allen/aesm/34-2s
http://www.brightcopy.net/allen/aesm/34-2
http://www.brightcopy.net/allen/aesm/34-1
http://www.brightcopy.net/allen/aesm/33-12
http://www.brightcopy.net/allen/aesm/33-11
http://www.brightcopy.net/allen/aesm/33-10
http://www.brightcopy.net/allen/aesm/33-09
http://www.brightcopy.net/allen/aesm/33-8
http://www.brightcopy.net/allen/aesm/33-7
http://www.brightcopy.net/allen/aesm/33-5
http://www.brightcopy.net/allen/aesm/33-4
http://www.brightcopy.net/allen/aesm/33-3
http://www.brightcopy.net/allen/aesm/33-2
http://www.brightcopy.net/allen/aesm/33-1
http://www.brightcopy.net/allen/aesm/32-10
http://www.brightcopy.net/allen/aesm/32-12
http://www.brightcopy.net/allen/aesm/32-9
http://www.brightcopy.net/allen/aesm/32-11
http://www.brightcopy.net/allen/aesm/32-8
http://www.brightcopy.net/allen/aesm/32-7s
http://www.brightcopy.net/allen/aesm/32-7
http://www.brightcopy.net/allen/aesm/32-6
http://www.brightcopy.net/allen/aesm/32-5
http://www.brightcopy.net/allen/aesm/32-4
http://www.brightcopy.net/allen/aesm/32-3
http://www.brightcopy.net/allen/aesm/32-2
http://www.brightcopy.net/allen/aesm/32-1
http://www.brightcopy.net/allen/aesm/31-12
http://www.brightcopy.net/allen/aesm/31-11s
http://www.brightcopy.net/allen/aesm/31-11
http://www.brightcopy.net/allen/aesm/31-10
http://www.brightcopy.net/allen/aesm/31-9
http://www.brightcopy.net/allen/aesm/31-8
http://www.brightcopy.net/allen/aesm/31-7
https://www.nxtbookmedia.com