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.

1. Oleksandr Mazurenko
CEO, Covert Wireless Communications

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.

7. Tests. Testbed
TX - Prototype CWC_VHF 110-600 MHz.
RX - SDR USRP B200 + GNURadio

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

9. Tests. Hidden data transmission

10. Tests. Hidden data transmission

11. Tests. Hidden data transmission

12. Tests. Hidden data transmission

13. Tests. Narrowband interference immunity

14. Tests. Narrowband interference immunity

15. Tests. Narrowband interference immunity

16. New opportunities
Narrowband and wideband link simultaneous operation
Radiation power increasing in ISM bands
ΔP= 40-45dB

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)

18. New opportunities
Hidden transmission over short distances
Power adaptation
Р<1uW, R<100m (330 ft)

19. Wireless communication services
• Military communications
• Security communications
• Drones control
• Remote control

20. Prospects
• Spatio-temporal synchronization algorithm implementation / Code
Division Duplex application
• Complex network structures realization (Mesh, Ad-hoc)
• Encoder optimization / Data rate increasing
• Parallel streams encryption implementation
• High performance devices of 2,4GHz ISM band developing

21. THANK YOU!