DIPOL Weekly Review - TV and SAT TV, CCTV, WLAN
No. 40/2014 (Dec. 8, 2014)
First one-terahertz solid-state amplifier. The Defense Advanced Research Projects Agency (DARPA), a part of the U.S. Department of Defense, can boast of reaching a terahertz "speed" of an integrated circuit. The amplifier operates at the frequency of one terahertz (1.000.000.000.000 Hz), ca. by 18% higher than that of the previous record-breaker (850 GHz achieved in 2012). Computers and radio systems operating in the terahertz frequency range would have a great potential - from creating tricorders (multifunction hand-held devices used for scanning, data analysis and recording) and other high-precision scanners, to "terra-fast" wireless networks, hundreds times faster than those working in the GHz bands. Of course, the main field of interest of the agency are military applications. The terahertz spectrum is the range of sub-millimeter electromagnetic waves, T-rays, which are very promising for use in radar systems, other detection/reconnaissance and imaging systems, and in wireless networks with extremely high bandwidth. Due to the wavelength of less than one millimeter, terahertz waves can provide a much higher resolution in such systems. The information capacity of such medium makes it ideal for transferring large amounts of data.
Although it's just a media celebration of the big scientific achievement, DARPA and its 1 THz integrated circuit have been entered in the Guinness Book of Records
The chip has been developed by Northrop Grumman Corporation, taking part in the DARPA's Terahertz Electronics program. It is a 10-stage monolithic amplifier manufactured in standard CMOS process technology. The specific details are not available, but it is believed that the structure is made of indium phosphide (InP), capable of switching at much higher frequencies (and at higher power levels) than devices made of typical semiconductors such as silicon or gallium arsenide. At 1 THz, the chip shows a measured gain of 9 dB. It is an unprecedented value in the terahertz range, where, according to Dev Palmer from DARPA, "gains of six decibels or more start to move this research from the laboratory bench to practical applications ...". An amplifier chip is just one piece needed to reach the terahertz threshold. But it is a basis for building generators of the T-rays. To take full advantage of such waves it is necessary to complete the generators with antennas and receivers, to form transceivers. Although the DARPA agency has not gone so far yet, the achievement is already impressive and groundbreaking.
Measurements of DVB-T signals - MER. The signal level is not the only parameter which must be taken into account in measuring DTT (DVB-T) signals. At least equally important are MER Modulation Error Ratio (MER) and Bit Error Rate (BER). MER can be treated as a measure of the distance of the received signal to the digital cliff. Without knowing this parameter, the antenna installer cannot guarantee stable reception in adverse weather conditions or other situations when the signal can fluctuate (e.g. interfered by a passing truck). It is necessary to ensure adequate safety margin to avoid this type of situations.
The cliff effect in digital DVB-T. In the case of a digital signal, the boundary between an ideal image quality and loss of reception is very sharp. The recommended and minimum values of MER required for proper reception depend on the modulation technique. In the case of 64-QAM modulation, they are 31 dB and 26 dB, respectively.
Digiair Pro R10510 is a cost-effective signal meter that has been designed to assist installers in adjusting TV antennas. It measures parameters of analog TV and digital DVB-T - COFDM signals, which is necessary for diagnosing antenna systems. The biggest advantage of this meter is the ability to measure bit error rate (BER) and modulation error ratio (MER) of digital signals.
The first step to intelligent building. Exta Free is a wireless platform for control of electrical appliances in households, offices, as well as in some industrial facilities. The system comprises a range of cooperating devices communicating in the 868 MHz band. An important advantage of solutions based on Extra Free devices is simplicity of installation and use.
Proven, economical and comfortable system for control of home electrical appliances can be enriched with "intelligence" through the use of the F5001 Mini Controller Exta Free EFC-02. The system may control lighting, heating, air conditioning, window blinds and other home appliances. Thanks to the mini controller, the users can manage the home system not only by radio transmitters, but also through smartphones or tablets. Comparing the system with similar solutions, it ensures fast and easy installation plus intuitive operation - all for low price. It can also be built step-by-step, with a minimum amount of installation, time and cost.
An example of a mini-system:
The ROP-01 F5211 receiver/relay is controlled by 8-channel wireless remote control P-256/8 F5118 and 2-channel wireless remote control RNK-02 F5101 (switching on/off the light sources). The controls can also switch on/off the RWL-01 F5220 wireless light switch and remotely controlled AC power outlet RWG-01 F5224. With the use of the F5001 Mini Controller Exta Free EFC-02, the users can control all Exta Free components from their handhelds (after installing dedicated app).
Currently, the most popular types of single-mode fibers in FTTx systems are G.652D and G.657A. These same types of fibers are used in pigtails. It is worth noting that if the regulations require the use of a certain standard, say G.657A, the same fiber should be used in the pigtails spliced to the fibers. Otherwise, the installation would not comply with the specification.
More information on various kinds of optical fibers can be found in the Optical fiber standards article.
Damage to wires in alarm systems. Wherever possible, the cabling of an alarm system should be installed on the stage of construction of the building, before plastering. The recommendation is important both due to aesthetic and safety reasons (hiding the cables from the reach of potential intruders). Other components of the alarm system (such as the G2045 intruder alarm control panel, G3216 motion detectors, G2152 keypads) are usually installed after the completion of the construction work inside the building, in the previously planned and prepared locations.
It may happen that after the installation of the entire system, the devices do not work, despite the use of the new wiring. The problem can be caused by the carelessness of the construction workers (a damage to the wiring) or even by the installers themselves (e.g. during drilling mounting holes for detectors, keypads etc). In any of these situations, the installers have to test the faulty cabling, to locate and eliminate short-circuit or break failures. As a result, the system should start working properly, or there is another reason of improper operation, mostly an installation error.
The diagrams below illustrate the test procedures for break and short-circuit failures in a multi-core cable or wire bundle.
The diagram of the wires for short-circuit test
In the first case, all the wires of the cable or wire bundle should be connected together on one end of it. The test can be performed with any ohmmeter/multimeter, by testing circuit continuity between the first wire and the rest of them (5 measurements for 6-wire cable).
In the second case, the wires are disconnected, and the purpose of the test is to check the cable for a possible short circuit. A short circuit can be detected by measuring the resistance between the wires in the following sequence:
- between 1 and 2, 3, 4, 5, 6
- between 2 and 3, 4, 5, 6
- between 3 and 4, 5, 6
- between 4 and 5, 6
- between 5 and 6
The continuity of all wires in the first test and no short circuit in the second mean that the cable is OK.
Mobile Protect DVRs - browsing of recordings. The use of SD cards as the storage media in the Protect 104 M80104 DVR allows for easy and fast access to the stored data - it is enough to take out the card from the DVR and insert to the card reader in a PC. In need of archiving, the user does not have to connect a laptop directly to the DVR in the vehicle.
After inserting the card into a laptop, the recordings can be played back using the supplied CMS software. The software, in addition to searching and playing back video recorded from cameras, can generate the map of the journey, create charts of acceleration and find the moments of activation of alarm inputs. Using Google maps, the application can generate the route of the car displayed based on GPS coordinates. When playing back recordings, the position of the vehicle is shown on the map.
If necessary, the CMS software enables the user to export any portion of the recordings in AVI or mp4 format, "understandable" for any video player. To change the selected file into AVI format, the user should click on the AVI icon.
Compact IP camera Signal HDC-210P K1815 is equipped with 1/2.8" SONY CMOS Exmor sensor with resolution of 1920 x 1080 pixels (Full HD) and sensitivity of 0.1 lx (B/W). The focal length of the built-in varifocal lens can be adjusted within 2.8-12 mm range. The resource CD-ROM provides free CMS software for configuring and managing up to 64 Signal IP cameras. The utility automatically searches the cameras in the Ethernet network and allows for quick and easy configuration of the monitoring system.
IP NVR Signal HD 2704 K2704 is a modern 4-channel low-cost IP network video recorder dedicated for small IP CCTV systems. This standalone NVR with VGA and HDMI outputs can be directly connected to a monitor for live monitoring and playing back archives, without a need for an additional computer.
Compact IP camera Signal HDC-110P K1806 is equipped with 1/2.8" SONY CMOS sensor with resolution of 1920 x 1080 pixels (Full HD) and sensitivity of 0.1 lx (B/W). The focal length of the built-in lens is 3.6 mm, the camera is very small.
Dec. 1, 2014 - DIPOL Singing Robot at Cyberiada 2. The Museum of Technology (Muzeum Techniki i Przemysłu NOT) in Warsaw, Poland, located in the Palace of Culture and Science, held Interactive Robot Festival, Cyberiada 2. Such an important meeting of cyber personalities could not be missed by the DIPOL Singing Robot, attracting many fans with its charming voice. In addition to our robot, the visitors of the festival could see e.g. flying drones, cyber fish and even the famous Martian rover, Hyperion. The event took place from 29 November - 7 December 2014.
New Library titles
How to make use of alarm sensors in a video surveillance system? The appropriate configuration of video recording in a CCTV system is especially vital in the case of small disk space. Usually, the most effective way of using the space is triggering the recording by motion detection, the feature embedded in security cameras or in the DVR. In some cases it is not the ideal solution, since the detection based on image analysis may cause many false alarms and unnecessary recording. A good idea is to use alarm sensors connected to the alarm inputs of the DVR (usually available in NO and NC versions). Hikvision DVRs with alarm inputs can record selected channels assigned to individual inputs. Such configuration of video recording ensures very high operational reliability and saves disk space.
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No. 39/2014 (Dec. 1, 2014)
Echo - Amazon's concept of home computers. Distribution of surveillance video from two CCTV cameras as a DVB-T channel....
Echo - Amazon's concept of home computers. Distribution of surveillance video from two CCTV cameras as a DVB-T channel....
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