Can be downloaded here: https://drive.google.com/open?id=0B5J_auuoZpgbZTFzLWJhM3FiUW8
Topic: ”Modern devices with spread spectrum application opportunities for wireless communications services performing”
Theses:
- Technologies and devices of “Covert Wireless Communications”.
- Test results of new devices of the company.
- Features of new devices of the company.
- Opportunities and prospects of wireless communication services based on products of the company.
2. Content
• Technologies and devices of “Covert Wireless Communications”.
• Test results of new devices of the company.
• Features of new devices of the company.
• Opportunities and prospects of wireless communication services based
on products of the company.
3. Technologies. Encoding/Modulation
The main data transmission principle consists in waveforms using in form
of Code Hoping CDMA. The most suitable case for this is Multichannel
M-ary Bi-Orthogonal Keying original channel encoding method.
(http://infotelesc.kpi.ua/article/view/47126)
Data
Key
Orthogonal Sequences
Set Generator
Sequence Selector
RF Frontend
4. Technologies. Algorithms. Encryption
Universal Orthogonal Sequences Fast Generation/Transform Algorithm
Allows to decrease computational requirements and DSPU cost radically
12 GIPS (FPGA) → ↓150 times → 80 MIPS (ARM Cortex M4/7)
Allows to implement new PHY layer encryption – Parallel Streams Encr.
One binary stream
(crypto analyzable)
16 parallel streams
(non analyzable)
5. Technologies. Another issues
Analogue / Prototype techniques: IEEE 802.11b, GPS PHY layer.
Advantages:
•Each next data symbol is transmitted by different orthogonal spreading
sequence
•Fast changing of channel encoding algorithm
•Does not require other encryption techniques
•Does not require outer synchronization channels
•Does not require carrier signal acquiring
•Allowable absolute frequency instability δf = 0,78х10-6
6. Devices. Parameters
Radio modem CWC_VHF 110-600MHz.
Parameters:
• Frequency range, F = 110-600 (433.92) MHz,
• Bandwidth, ΔF = 2 MHz,
• Radiation power, S = 0 dBm,
• Spread Spectrum Multiplier, М = 1024х2 (+33dB power
gain),
• Data rate, R = 9,6 kbps,
• Maximum transmission range ~1,5 km (~0,9 mile),
• Power consumption, P < 1 Watt.
8. Tests. Results
At next dynamic figures comments are absent for better visual perception.
Each figure consists of 3 part (from top to bottom): 1. RX signal time
domain; 2. RX signal detector response; 3. RX signal spectrum.
There are 4 figs for hidden transmission case and 3 figs for narrowband
interference (FSK signal) immunity case in next order:
•Primary/Reference case – signal are captured from modem ANT output;
•Hidden transmission with 60dB path loss, no gain;
•Hidden transmission with 60dB path loss, 60dB gain
•Hidden transmission with 120dB path loss, 60dB gain
•Reference case for interference immunity test, SINR = 0 dB
•Signal receiving in conditions of NB interference presence, SINR ≈ -30dB
•Signal receiving in conditions of NB interference presence, SINR ≈ -40dB
17. New opportunities
Hidden transmission between distant objects
Signal envelop is recognizable
Signal spectrum is recognizable
Hidden transmission
1mW
<100m (330ft)
<300m (1000ft)
<1500m (0,9 mile)