DIPOL Weekly Review - TV and SAT TV, CCTV, WLAN

Billion "frames" per second - a camera quick as light.

Researchers from MIT have developed a prototype camera capable of capturing images at the speed of light. Apart from its technological merits, the admirable thing is the estimated cost of this device - only about 500 USD.

Such a low price has been achieved mainly through the use of well known technology called "Time of Flight" (ToF), which is employed, e.g. in the latest generation of Microsoft's game consoles - Xbox One, just hitting the market. The Kinect sensor reacting to gestures of players is based on this method. The mechanism of ToF involves sending modulated light pulses and measuring the time of their return to a sensor placed in the device. Due to the high speed of light, the sensor must operate at a very high frequency (that used in the camera from MIT operates at a frequency f = 1/1000000000 s, generating an image every 1 nanosecond). The times after which photons return to the device are determined by the distances to the objects and their depth, which can be used for 3D imaging.
The U.S. scientists, using appropriate coding techniques known from telecommunications engineering, solved problems of imaging translucent objects, as well as problems with operation in difficult weather conditions such as fog or rain, when the light is refracted and dispersed.

The capabilities of devices based on ToF technology are large - the camera can be used for example to generate images of objects outside ... the field of view.
In the picture: the image of the mannequin hidden behind the wall can be reproduced
on the basis of pulses reflected from the door.

The device recording reflected photons at Gigahertz frequency has been called by the innovators a "Nano-camera" and it is the second child of scientists from MIT working in this field. Already in 2011, they created a "femto-camera" recording images at speed of three orders of magnitude larger than the nano-camera. However, the cost of such a camera was also proportionally higher - about ... 500000 USD. The cameras differ in the kind of the generated light pulses and optical equipment. The expensive camera uses femtosecond impulses of light and laboratory-grade equipment, whereas the cheap device generates optical pulses on a continuous basis with a Gigahertz frequency.

The femto-camera designed by MIT Media Lab captures images
lasting 1*10(exp-12) s (one femtosecond).
Such period is comparable with that of thermal vibrations of atoms.

Aside from gesture control in interactive games, the potential applications of cameras based on "Flight of Light" technology include collision avoidance systems, gesture recognition systems for control of various devices, medical imaging.

Passive optical networks (PONs) - installation of distribution frames and boxes.

To distribute FTTH services throughout an apartment building, it is necessary to bring fiber optic cable to each subscriber. The most common method of cabling multifamily buildings is based on distribution frames mounted in basements, and distribution boxes installed on individual floors close to the riser. Independent fiber optic cables are run from the distribution frame to the distribution boxes on the floors. Then, optical fibers are led from the distribution boxes directly to termination boxes in apartments, e.g. ULTIMODE TB-02H L5302.

Distribution boxes are often installed in a confined space, so they should be small in size, easy to install and maintain. These requirements are met by ULTIMODE L5404 boxes allowing for easy organization of up to 4 fibers.

All the fibers distributed in a building go from a distribution frame usually located on the lowest floor (basement). It is the node which connects the internal network with external infrastructure. An example is the ULTIMODE TB-48B L5448 frame.

FTTH architecture in a building

Wireless remote control extender.

Remote controls of popular electronic devices can use different IR frequency ranges, so it may happen that some remote control extenders will not properly operate with specific devices. DIPOL has brought to the European market Signal DIR-300V remote control extender with FSK modulation. Thanks to a wide range of the retransmitted IR band, the extender can be used with majority of consumer devices (DVD/Blu-ray players, sat receivers, STBs, home theaters etc.), as well as with professional equipment in CCTV systems, for remote control of DVRs/NVRs located in different rooms than the sites of the operators.

Wireless remote control extender Signal DIR-300V R94120 allows the user to control devices located in other rooms of the household or commercial facility. Elegant and compact design of the transmitter and receiver is well suited to modern home theaters etc. Thanks to FSK (Frequency-Shift Keying) modulation at 433 MHz, the range of the set is significantly larger compared to traditional extenders using analog AM modulation.

Typical application of the Signal DIR-300V R94120 IR extender

Protection of cable connections in CCTV systems.

A common problem with installing CCTV cameras is no place to hide the cable connections. It can be solved by application of installation boxes, but this solution is often not preferred due to esthetic reasons. A good idea is to use cameras allowing for hiding cable connections. An example of vandal-proof camera with that feature is v-cam 530 M10773.

The v-cam 530 M10773 camera has modular construction that provides ease of installation and resistance to weather conditions. The camera base has enough space to accommodate cable connections, whereas the detachable camera module is fully protected from environmental factors (IP68).

Thanks to high performance and modern look, the affordable and reliable camera is recommended for CCTV systems in prisons, banks, courts, consulates, airports etc.

Affordable, full-featured IP video surveillance.

DIPOL has introduced two models of cost-effective IP NVRs: Signal NVR K2708 and K2716. Respectively, they support 8 or 16 Sunell IP cameras (via ONVIF protocol), or the same numbers of Signal cameras (with full integration). The both models can record video streams with resolution of 1080p at 25 fps from each camera, on the condition that the total bitrate of all video streams does not exceed 32 Mbps for K2708 or 64 Mbps in the case of K2716. Such high recording performance is possible thanks to the use of two video streams. The preview in screen division modes does not need the full resolution of the component images, so they can be provided at lower bitrates, which saves the processing power of the CPU to support the Full HD recording.

Low-cost IP CCTV system with 1920x1080 recording resolution at 25 fps (Full HD)
composed of Signal K2716 IP NVR, Sunell K1698 and Signal K1810 cameras

Each of the NVRs can be directly connected to a monitor for live monitoring and playing back archives, without a need for an additional computer. With the included mouse, the user can setup the system by configuring display options, recording modes, playback and backup settings. The IR remote control supplied with the NVR can manage the system and switch the views from the cameras from a distance of several meters.
Remote access to the NVRs is possible via Internet Explorer or with the use of free CMS software that can be installed on any modern computer running Windows OS. Dedicated applications enable users to display surveillance video on Android, Blacberry, iPhone, Symbian, Windows Mobile smartphones.

Optimal WLAN cells - one or several APs?

There are a few ways to cover an area with WLAN signal, depending on the desired range and capability of the network.

The system (a) with three APs and three sector antennas (120°) can cover 6 times bigger area, providing service to 3 times more subscribers, compared to the system (b) with one AP and one omnidirectional antenna. In both cases, client devices should be equipped with antennas having gain corresponding to the distance from the base station.

The size of a cell should be chosen taking into consideration the expected number of users and terrain conditions, such as the shape of the land and various barriers like trees, chimneys, buildings etc.

November 29, 2013 - new seat in Czestochowa. It's been three months since our branch in Czestochowa moved from the old store in the 1 May street to the new location in the Independence 8 avenue. Now we are able to serve more customers in much more comfortable conditions. The customers praise the new place, because it's easier to drive and park there. Thirsty guests can grab a delicious coffee and take advantage of our consulting professionals helping to resolve any problems associated with antenna, telecommunication, and CCTV systems.

Modernization of antenna system in an apartment building. One of Krakow's housing associations decided to modernize the shared antenna system for the reception of DVB-T and FM radio. The four-story building has four staicases, each floor has four apartments... more

Diagram of the antenna system in the multifamily building