My Cart is empty



DIPOL Weekly Review - TV and SAT TV, CCTV, WLAN
No. 1/2014 (Jan. 6, 2014)
The risk of inaudible communication between... computers. Michael Hanspach and Michael Goetz from the Fraunhofer Institute for Communication, Information Processing, and Ergonomics in Germany have created a mesh network between laptops using for the data transmission high-frequency audio signals emitted by the speaker of one device and received by the microphone of the other.
The tests have shown that the messages between the computers can be transmitted via audio signals at frequencies close to the upper limit of the human hearing range (about 20 kHz). The transmission took place between Lenovo T400 laptops running Debian operating system and equipped with 82801I sound processor from Intel Corporation, enabling transmission and reception of acoustic signals at frequencies from 0 to 35 kHz. The obtained transmission speed was about 20 bits per second, at distances up to 19.7 m.
The "audio network" built for the purpose of the experiment consisted of five laptops. The researchers wanted to demonstrate that such a network is capable of transferring confidential information that does not require a large bandwidth (e.g. access keys, credit card information, passwords, etc.). The engineers responsible for the project developed a special routing protocol for the system allowing for ad-hoc connections between the devices with intermediate stages. The success of the tests is can be a warning that even devices not connected to the Internet can communicate and transfer information.
Have the German researchers discovered a new and effective method to steal confidential information from electronic devices? So far, it might seem that the physical disconnection (both wired and wireless) of a computer from the Internet ("air gap") guarantees 100% security of the contained information. But it has been proven that using ultrasonic signals, these data may "leave" the devices in a completely unexpected way ... It is enough to prepare a dedicated virus.
An important feature of this communication system is its resistance to typical noise sources. The biggest limitation is its maximum data transfer speed of 20 bits per second. However, such limited bandwidth is fully sufficient for the transmission of passwords for bank accounts, electronic mail, or social networking sites. But the whole "spying system" can only work if the computers are infected. It shows the importance of antivirus and anti-spyware protection.
Changing the location of the server room. After the construction of a new building, the owner of a production plant decided to move the telecommunications facility. The previous location (production hall) did not provide a sufficient level of safety and environmental conditions required for the servers.
The equipment includes devices supporting CCTV system with 8 analog cameras (two of them are PTZ devices) deployed in the building, and network devices (LAN node).
Web Smart Switch: TP-LINK TL-SL2210WEB 8+2G 1xSFP RACK Fiber Optic Video Converter ULTIMODE V-216D (single-mode, WDM, 16x video, 1x data, RACK 19'') SFP Transceiver: ULTIMODE SFP-203G 2xLC (two single-mode fibers up to 20 km)SIGNAL 19Ethernet Media Converter M-203G (for two single-mode fibers up to 20km)Fiber Optic Video Converter ULTIMODE V-216D (single-mode, WDM, 16x video, 1x data, RACK 19'') SIGNAL 19Spare Cable Storage Rack ULTIMODE-X01-A (adjustable)Spare Cable Storage Rack ULTIMODE-X01-A (adjustable)Outdoor Cable: ULTIMODE OMT-108SM-A (multi-tube 6+1, 1x8xG.652D)
Optical link between the old and new building ensures LAN connection and access to the Internet,
as well as transmission of images from 8 analog cameras
The signals are transmitted between the buildings with the use of outdoor fiber optic cable. The fibers at both ends have been terminated in accordance with the specifications of the fiber optic modules. The video signals from the analog cameras are converted into optical form by the 16-channel fiber optic video converter ULTIMODE V-216D L2921. It will allow for further expansion of the video surveillance system in the future. The TP-LINK smart switch N29949 with SFP ULTIMODE L1415 module provides gigabit connectivity. The new server room has been equipped with ULTIMODE L11025 media converter. The ends of spare fibers have been protected and the cable reserves are stored on the ULTIMODE-X01-A L5504 racks.
Distribution of surveillance video in digital form (DVB-T) in multiswitch systems. Modern SMATV systems enable users to receive FM radio, terrestrial and satellite TV broadcasts, all through one master antenna set located on the roof of the building.
The sense of security of the residents can be increased by allowing them to view images from security cameras deployed in the building and its surroundings. The video signals from each camera can be injected to the SMATV system through the use of a dual DVB-T modulator mdx420 R82518. The residents can watch the CCTV video on their TVs connected to the multiswitch system, just by selecting the appropriate DVB-T channels.
Steel Satellite Dish: TRIAX 100 TD (100cm, dark gray)Outdoor Compact Camera: n-cam 670 (day/night, D-WDR, 650TVL, Sony Effio-E, 0.03 lx, 2.8-12mm, OSD, IR up to 30m) Outdoor Compact Camera: n-cam 670 (day/night, D-WDR, 650TVL, Sony Effio-E, 0.03 lx, 2.8-12mm, OSD, IR up to 30m) Universal QUATRO LNB: TRIAX TQT 006DVB-T Modulator TERRA mdx420 (2xAV/COFDM encoder & RF modulator)Four-channel Amplifier: Terra at440 (UHF, DVB-T, AGC) DIN Rail Power Supply DR-60-12 (12VDC/4.5A, for Terra at/mt/ma modules)UHF TV Antenna: DIPOL 44/21-69 Tri DigitAmplifier for 5-input multiswitches: Terra SA 51 Subscriber Terminal Outlet: Signal R-TV-SATSubscriber Terminal Outlet: Signal R-TV-SATSubscriber Terminal Outlet: Signal R-TV-SATMultiswitch Terra MV-524 (5-in, 24-out) - with IF gain adjustmentMultiswitch Terra MV-524 (5-in, 24-out) - with IF gain adjustmentMultiswitch Terra MV-524 (5-in, 24-out) - with IF gain adjustmentSAT/TV TAP: Terra SS-520SAT/TV TAP: Terra SS-515
Diagram of a multiswitch system distributing satellite TV, DVB-T and surveillance video in a building with 3 staicases (each with apartments equipped with total number of 24 outlets)
The multiswitch system consists of Terra SD-520 R70518, Terra SD-515 R70517 SAT/TV taps and 3 multiswitches MV-524 R70724. Terrestrial DVB-T broadcasts are provided by the four-channel amplifier Terra at440 R82511 equipped with ultra-selective SAW filters. The images from two security cameras are injected into the distribution system by the dual Terra mdx420 R82518 modulator (as one DVB-T multiplex).
3D DNR function in analog CCTV cameras. The purpose of an image sensor is to change the light falling onto the imager to current/voltage proportional to the light intensity. Theoretically, if the light does not reach the sensor, the device should not generate any signal. In practice, as the result of imperfections of electronic components and thermal ("dark") noise, the imager generates some noise. Although the noise is always present, it is particularly evident in the absence of illumination. It is characterized by the signal to noise ratio (S/N).
The function that can limit the noise level visible in images is 3D DNR (3-Dimensional Digital Noise Reduction). This function compares a given video frame to the subsequent frames. If the result of this analysis shows a difference between the images resulting from noise, it removes noisy fragments, replacing them with the equivalent from the frame with better quality.
A comparison of the image from a camera with switched-off (on the left)
and switched on (on the right) 3D DNR function
We offer the following cameras with 3D DNR function: M10773, M11225, M10780.
Compact IP camera Signal HD-200 (2MP) compliant with ONVIF standard. IP CCTV systems with NVRs and IP cameras are the growing part of the video surveillance market. However, it is often difficult or even impossible to integrate IP devices from different manufacturers into one system.
To solve the incompatibility problems, the industry leaders took the initiative called Open Network Video Interface Forum (ONVIF), aimed at coordinating efforts to set common standards in this field. ONVIF-compliant devices ensure flexibility in building IP video surveillance systems due to interoperability of equipment from various manufacturers. By standardizing the digital interfaces of the IP CCTV devices and unifying compression and transmission of video streams, configuration and control procedures, event handling etc., the user is given an easy to manage and uniform platform.
Compact IP Camera: Signal HD-200 Full HD (2MP) with IR Illuminator
Compact IP camera Signal HD-200 (2MP) K1810 - excellent image quality and support for ONVIF
Signal HD-200 K1810 and Sunell K1634, K1637, K1660, K1680, K1691, K1695, K1698 cameras can be easily integrated with any IP devices and software platforms supporting ONVIF standard, such as Signal K2708, K2716 and Hikvision K2204, K2208 IP NVRs, or NUUO K3104, K3108, K3116 surveillance software packages.
Transmitting images from megapixel cameras in city video surveillance systems. The resolution of analog video is limited by TV standards (PAL, NTSC), typically in analog CCTV systems to 704 x 576 pixels (4CIF). Such a limit does not apply to IP systems equipped with megapixel cameras. For example, FullHD models K1634, K1691, K1680, K1695, K1698 provide images with five times more pixels, and the 5MP K1637 camera with 12 times more pixels. The images can be enlarged many times (depends on the actual resolution), still preserving details needed for identification purposes (face recognition, reading vehicles' license numbers etc).

ULTIAIR equipment, with throughput up to 150 Mbps, perfectly solves the problem of data transmission. Wireless solutions can considerably lower the costs of implementing these modern systems. They eliminate the need for building cable infrastructure (e.g. the cables from the cameras to the monitoring center, even several kilometers long, usually with necessary conversion to optical form). The cameras are connected to ULTIAIR devices, the monitoring center is also equipped with a ULTIAIR device which receives the data wirelessly.
Both for the transmission of video streams and PTZ commands there can be used access points integrated with antennas, powered with the use of PoE technology. There may be employed sector antennas that will create easily manageable sectors.
Wireless Access Point: ULTIAIR 323KC 150Mb/s 802.11nIP High Speed Dome Camera: Sunell SN-IPS54/70DN/Z18W (1.3MP, ONVIF)IP High Speed Dome Camera: Sunell SN-IPS54/70DN/Z18W (1.3MP, ONVIF)Wireless Access Point: ULTIAIR 323KC 150Mb/s 802.11nIP High Speed Dome Camera: Sunell SN-IPS54/70DN/Z18W (1.3MP, ONVIF)IP High Speed Dome Camera: Sunell SN-IPS54/70DN/Z18W (1.3MP, ONVIF)Wireless Access Point: ULTIAIR 417SB 150Mb/s 802.11nWireless Access Point: ULTIAIR 417SB 150Mb/s 802.11nWireless Access Point: ULTIAIR 417SB 150Mb/s 802.11nWireless Access Point: ULTIAIR 323KC 150Mb/s 802.11nWireless Access Point: ULTIAIR 323KC 150Mb/s 802.11nWireless Access Point: ULTIAIR 323KC 150Mb/s 802.11nIP High Speed Dome Camera: Sunell SN-IPS54/70DN/Z18W (1.3MP, ONVIF)IP High Speed Dome Camera: Sunell SN-IPS54/70DN/Z18W (1.3MP, ONVIF)
IP CCTV system for cities based on ULTIAIR devices
New products offered by DIPOL
TV Optical Transmitter: TERRA mo418 4D31 (1x6dBm, 1310nm)
TV Optical Transmitter TERRA mo418 4D31 R82522 is used for transmission of television signals via optical medium. It converts input electrical signals within 47-2400 MHz range, fed with coaxial cable, into optical signal. The power of the optical signal is 6 dBm (4 mW), which is sufficient for feeding several to ten or so nodes (depending on the sensitivity of the receivers).
Twin Channel Amplifier: Terra at420 (UHF, analog TV & DVB-T, AGC)
Broadband Masthead Amplifier ARM-102M R85210 is dedicated for individual antenna installations and small shared antenna systems with up to a dozen or so outlets. The gain of the broadband (87-790 MHz) amplifier increases with the signal frequency, from 7 dB to 11 dB. The amplifier has two outputs for direct connection of two outlets for two televisions, or for connection to two networks, each distributing the output signals to several outlets.
Pole/Post Clamp MH-625 (Ø max 105mm, white)
Pole/Post Clamp MH-625 M5172 allows for mounting one or two camera brackets (on both sides) on a pole/post with diameter up to 105 mm. The clamp is galvanized and powder-painted.
New Library titles
DIPOL for education - SMATV and CCTV systems. This article is dedicated to teachers and students of technical schools with electronics courses. It contains a set of materials that can be used in the implementation of a training program for SMATV and CCTV technologies. We present solutions for laboratory workstations focused on the key issues related to installing TV, SAT TV and CCTV systems. We pay attention to what each installer should know about the systems and suggest the use of free SatNet software designing SMATV systems. In one place we also gathered links to articles useful in the learning process... more
Worth reading
How to increase the sensitivity of security cameras - "Sense-up". The range of IR LEDs in CCTV cameras is limited, usually to 20-30 meters. Stronger IR light sources cause overexposure of objects located close to the cameras. Therefore, many installers look for solutions without infrared illuminators which can provide acceptable image quality in poor lighting conditions. In this case, an option is to use cameras with slow shutter speeds. The function can significantly increase the sensitivity of the cameras... more
The effect of Sense-Up function (on the right)
Online cameras - check out our equipment!
Online cameras - check out our equipment!
If you are interested in receiving our weekly Newsletter by e-mail, enter your e-mail address: