No.38/2016 (Nov. 21, 2016)
Telescope with Polish cameras will take care of the safety of the Earth.
The European Space Agency plans to build a system of ground-based telescopes, responsible for observing the cosmos in search of objects that might threaten our planet. Such an early warning system is to detect bodies whose trajectories are on a collision course with the Earth. This should prevent a disaster similar to that which happened 66 million years ago, when a massive asteroid struck our planet forming a 180-kilometer crater in the region of the present-day Gulf of Mexico. The result of the disaster was the extinction of more than 75 percent of all species of plants and animals. 108 years ago, a meteorite over Siberia felled trees within a radius of 40 km. This is known as the Tunguska event. On February 15, 2013, a meteorite with a diameter of about 17 meters and weight of up to 10,000 tonnes entered the Earth's atmosphere over the southern Urals. Before the meteorite hit the ground, it had burnt down almost completely. The generated shock wave damaged 7.5 thousand buildings and caused injuries to 1200 people.According to Dr. Ed Lu from NASA, the situation that took place in Chelyabinsk may repeat approximately every 10-20 years, and what worse, the objects can be much greater. Already an object with a diameter of just 140 meters could cause an explosion with the power of 150 million tons of TNT, more than 300 times stronger than in the case of the meteorite in Chelyabinsk.
To be able to react in advance, researchers are working on systems that should protect our planet against threats from the outer space. The European Space Agency (ESA) has launched the Space Situational Awareness (SSA) program. It involves overseeing the space and tracking space objects. The task will be supported by NEOSTEL ground based network of telescopes detecting various objects threatening the Earth.
Telescopes observing space
The heart of such a telescope will be supersensitive CCD camera used for observation and image analysis. This element is developed and manufactured by Polish company Creotech Instruments S.A. In October this year they finished the first of the cameras. So far, they test the camera in laboratory conditions, without a special lens system. But already in 2017 it will be put into operation in the first telescope.
The telescope will be equipped with multiple cameras to capture the widest possible picture. According to the ESA, further 20 cameras will be needed in 2018. Probably in 2019, the project will grow to 30 telescopes of this type, equipped with more than 200 Polish cameras. The cameras are cooled to -50°C and kept in ambient pressure conditions close to vacuum. Under these conditions they are able to spot an object of the size of a tennis ball at a distance of 1000 km. "Such a system will detect in advance objects in space that could threaten Earth and artificial satellites" - promises Dr. Grzegorz Brona, the CEO of Creotech Instruments S.A.
EmiMaps app - DVB-T coverage in Poland.
EmiMaps is a new tool created by Emitel - the operator of terrestrial broadcasting infrastructure in Poland. The tool is dedicated for anyone who installs or modernizes DVB-T antenna installations. The EmiMaps application shows the estimated coverage of DVB-T transmitters operated by EmiTel. It helps to determine the reception conditions of MUX-1, MUX-2, MUX-3 and MUX-8 digital multiplexes in any location in the country, and to choose the right antenna and its direction. The interface of the app consists of four tabs, opening searching, location, antenna setup, and information (list of transmitters) utilities. For proper operation, the app requires access to the Internet and recommends the employment of the positioning and compass sensors of the smartphone.EmiMaps - the subsequent stages of finding the transmitter's location and the direction of reception:
- choose the multiplex and determine your location - select the transmitter - the antenna symbol on the screen of a horizontally laid smartphone will indicate the direction to the transmitter, below there is data concerning the transmitter, polarization, terrain profile between the transmit and receive antennas | |
In order to evaluate the possibility of DVB-T signal reception, select the required multiplex and enter the address of the reception point. You can also use automatic positioning function (GPS), or move the house icon to the desired place on the map. When you set the location, the app will show the expected coverage of the multiplex in the reception point. The application allows you to scale and scroll the map. Moving the reception point (house icon) to another location will automatically show the coverage for the new location. By clicking the transmitter icon you to read the detailed parameters of the broadcast signal.
The application for Android devices is available in GooglePlay store. EmiMaps for PCs is available at EmiMaps.emitel.pl. A version for iOS devices should be available soon.
Which antenna for LTE?
Long Term Evolution (LTE) is currently the fastest standard of data transmission in cellular networks. The download speed can reach 326 Mbps, the upload speed 86 Mbps (20 MHz channel, 64QAM modulation, MIMO 4x4). LTE technology is flexible, both in terms of frequency and width of the transmission channel. Depending on requirements, LTE networks in Europe operate at frequencies from 700 MHz (in rural areas - broader range) to 2.6 GHz (metropolitan areas - better propagation in buildings). It should be noted that LTE uses MIMO (Multiple Input Multiple Output) technology, which allows the transmission of signals using multiple antennas or antenna arrays.As mentioned above, LTE networks can operate over a wide frequency range. Currently they use 800 MHz, 1800 MHz, 2100 MHz and 2600 MHz bands, with the perspective of 700 MHz band (e.g. in Poland, within a few years).
Before purchasing an antenna, please contact your operator for information about the nearest base stations and the transmission parameters used. Additionally, you should make sure of the type of connector used in your modem or router. The antenna has to be connected to the device via a suitable antenna connector.
When selecting an external antenna, the user of a modem should make sure whether the device supports MIMO technology (has two antenna connectors). If so, it is necessary to use an antenna that also supports this standard. It is a simple way to achieve the maximum throughput. The maximum distance from the base station should not exceed 6 kilometers.
The ATK-LOG ALP LTE MIMO 2x2 A7054_10 operates within 800-3000 MHz range,
and it comes with 10-meter cables terminated with SMA plugs.
The antenna has been designed for use with LTE modems (with two antenna connectors),
cell phones, GSM, DCS, 3G modems.
and it comes with 10-meter cables terminated with SMA plugs.
The antenna has been designed for use with LTE modems (with two antenna connectors),
cell phones, GSM, DCS, 3G modems.
Optical fibers in CCTV - multimode or single-mode?
Generally, when selecting the equipment and cables, both the elements have to be compatible. If the connections between cameras and the switch are greater than 2 km, it is necessary to apply single-mode cables. Similarly to situations where one cable should transmit signals from dozens or hundreds of IP cameras. With such a wide band, the use of single-mode fibers should be a more preferred solution. The range of single-mode cables is broader, allowing for the selection of optimum cable, and the transmission line can be extended in the future beyond 2 km, if necessary.The difference in the price of multimode and single-mode devices, often served as an argument for the option of applying the former, nowadays is negligible, at least in the case of transmission equipment for LAN and CCTV systems. And the cost of multimode cables is even higher, due to a more complicated production process. So, all the arguments are for single-mode solutions (greater distance, higher throughput, lower price).
The most popular types of optical cables used in CCTV systems are universal cables with single-mode fibers. The picture shows Ultimode UNI-4SM-A L76004.
Advantages of choosing cables with single-mode fibers:
- easier choice due to a broader range of the cables on the market
- ability to transmit signals at distances of tens of kilometers using typical equipment
- lower prices compared to multimode fibers due to lower production costs
- higher throughput capacity
- availability of cables with small bending radius, from 7.5 mm
Drawbacks of choosing cables with single-mode fibers:
- different versions of fibers may cause problems with splicing, it is recommended to unify the cables in the system
- in exceptional cases and depending on the equipment it may be necessary to use fiber optic attenuators for short distances - the information should be found in the data sheet of transmitters and receivers, especially on the transmitter output power and the receiver sensitivity
Easy configuration of multiple devices in IP CCTV systems.
In one location there are often several IP cameras and/or NVRs. Most of the settings of the devices within one group are similar or even identical. Hikvision NVRs can be quickly configured by exporting a file with configuration settings from one device to the rest of them in the system.The import/export operations can be performed:
- locally via USB interface
- via the network:
- using iVMS-4200 software or a web browser - especially useful in the case of distant locations of the NVRs
- using Batch Configuration utility (part of Hikvision Tools)
Channel-zero Encoding in Hikvision NVRs.
Sometimes users need to preview multiple channels of NVR in real time using a web browser or CMS client software. To reduce bandwidth requirements without compromising the quality of the recorded video, that is, without the impact on the encoding parameters of the main stream and sub stream, Hikvision NVRs provide Channel-zero Encoding option. With this function, the user can preview images from 16 channels in one window of internet browser or the client software. The settings of the function include the maximum bit rate (up to 2048 kbps) and maximum frame rate (1/16 - 22 fps). The function can be activated locally or via an internet browser.Activation of Channel-zero Encoding:
- locally: Main Menu -> Settings -> Live View -> Channel 0 Encoding
- remotely: Configuration -> Video/Audio -> Channel-zero
Broadband Cable Amplifier Terra HA-205R65 R82307 is equipped with output stage using Gal-As semiconductor components, working in push-pull mode. The amplifier has been designed for professional cable and MATV systems with return path/channel and allows for signal level adjustment and equalization in forward and return path. | ||
Waterproof Installation Box (540/310/145mm) R90607 is to be placed on a wall or pole. The box has 4 mounting holes. Inside the box, on the rear wall, there is easy-detachable mounting plate with size of 510x260 mm. The construction of the box is fully waterproof and the door, locked with cylinder lock, is protected with a rubber seal. The box has IP55 rating. | ||
Multimode Patch Cord PC-019D (2xSC-2xSC, OM2, 3m) L31130 is made of two parallel sections of multimode fiber optic cable with a length of 3 meter, terminated on both sides with two SC connectors. SC connectors feature simple matching (push-pull coupling with a snap) and rectangular cross-section allowing dense packing of the connectors on the panel. | ||
Worth reading
How a thermal imaging camera works? "Normal" analog or IP cameras used in video monitoring systems capture visible and (usually in night mode) near infrared radiation (in total: 300-950 nm) reflected from the objects in the field of view. The sources of the radiation can be the daylight or artificial lighting systems, including IR illuminators. Thermal imaging cameras work properly without any additional source of lighting. Each body with a temperature above absolute zero emits infrared radiation. The infrared cameras may use wavelengths between 1-20 micrometers... >>>more