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

New CMOS sensors produce better images.

In August this year, Canon Inc. announced the development of two cutting-edge image sensors based on CMOS technology. The first one is CMOS sensor with 120 million pixels (120 Mpx), the second - a giant of the 202 mm x 205 mm size.

The 120 Mpx sensor with dimensions of 29.2 mm x 20.2 mm (APS-H size used in EOS-1Ds and EOS 5D cameras) has over 7 times the count of pixels that is used in the current commercial solutions. To visualize the resolution of the image generated by the new sensor - the number of pixels is 300 times higher than that of an SD TV picture (which means the possibility of ca. 17x linear magnification of any part of the original image for this quality level).

The second image sensor, due to its immense size (202 mm x 205 mm), will not be used in popular devices. The capability of operating in extremely low light qualifies it for military applications, mapping and weather services. In relation to the best commercial solutions it has 100 times greater sensitivity.

The latest developments of Canon show the potential of CMOS technology, not fully exploited in recent years.

From the left to the right: the structure of traditional FSI CMOS (Front Side Illumination),
BSI CMOS (Back Side Illumination), and OmniBSI-2 image sensors
- materials of OmniVision Technologies

But the revolution in the consumer and commercial CMOS imaging technology has been spreading since 2007, when OmniVision Technologies developed Backside Illumination - BSI or BI sensor. The sensor was characterized by twice the sensitivity and significantly lower noise compared to conventional FSI CMOS technology (Front Side Illumination).

OmniBSI Technology is the reversal of the regular CMOS technology - the image sensor is exposed to the light inside out i.e. from the side of the substrate. In contrast to conventional FSI technology, this solution eliminates the masking effect of metal and oxide elements of the structure necessary for its functioning, significantly improving sensitivity of the BSI sensor.

CMOS sensors produced in the new process can have better resolution and greater sensitivity. Currently, the largest manufacturers of image sensors (Aptina, Canon, OmniVision Technologies, Samsung, Sony) gradually implement their versions of that technology. This year, OmniVision Technologies developed OmniBSI-2 sensors (next generation) with 1.1 um pixels (instead of 1.4 um). Sony successfully develops its own BSI CMOS line (Exmor R), with 16.2 Mpx sensors to be implemented in this year's products. In the current quarter, Samsung will start production of its BSI CMOS sensors, S5K4E5 (5 Mpx) and S5K2N1 (14.6 Mpx).

Now, in the era of rapid development of multimedia applications, the technologies of capturing, recording , and transmitting images have become the core focus areas. The elements that largely determine the quality of pictures and/or video are image sensors. The image sensor converts the light passing through the lens of a still or a video camera into electrical impulses. Currently, there are two main technologies of the sensors, CCD and CMOS. CMOS technology is much cheaper, while CCD sensors can still offer greater sensitivity and higher resolutions. According to the report of Global Industry Analysts, in the coming years the sensor market will grow at least by 10% per annum. However, most of the growth will be in CMOS field, as the sales of CCD devices can increase by a maximum of 3%.

Antennas on the Renaissance trail.

In this country there are 12 sites included in the UNESCO list. It is over two times more than the global average. The hallmark of UNESCO world heritage site means that the world society states: this is something special and unique throughout the world, something that is our common heritage, which we should protect for us all - nations of the world.
Among such sites there are these historical gems, combining Renaissance style in town and castle architecture.
In which country are these sites located? - The answer at the end of this issue.

How to install DVB-T tuner Signal HD-507?

How to install DVB-T tuner Signal HD-507? A short movie about the installation of exceptional DVB-T tuner.
It's really simple!

Cable TV on a few televisions - problems with the signal.

When choosing a device to split the signal from a cable television outlet, it is important to pay attention to the differences in requirements for digital and analog signals.
The acceptable level of digitally modulated signal (64QAM) is only 45 dBuV, while the minimum level of analog signal (AM) is 57-60 dBuV. There are also different minimum requirements for the C/N parameter: 43 dB for analog signal, 28 dB for digital signal (to obtain sufficiently low BER).

When choosing an amplifier, it is very important to select a device that allows adjustment of output level. As an example, an amplifier with fixed gain (usually about 20 dB) can pose problems in a situation where the both signals measured in a subscriber outlet have levels of 65 dBuV. 20 dB gai of the amplifier will allow to distribute the analog signal to a larger number of televisions, but the quality of the digital signal will be completely degraded, greatly exceeding the recommended level of 75 dBuV.

Another very important parameter, which should be considered when choosing a cable television amplifier, is noise figure of the device. For economic reasons, cable operators often provide subscribers with signals close to the minimum signal to noise ratios. The use of a cheap, low quality amplifier may cause an increase of signal level, but with a decrease in the C/N parameter preventing good reception. If the margin left by the operator is a few decibels, the key issue is to use a low-noise amplifier.

The products that meet the requirements for signal quality are TERRA amplifiers. For the described applications we can especially recommend the HA-129R65 R82316 amplifier with active return channel and noise figure below 6 dB, suitable for digital cable TV networks.

Building amplifier with active return path
TERRA HA-129R65 R82316

Economically and professionally with TREND DVRs.

CCTV installers often have to live up to the high expectations of customers that do not have a budget allowing to install top quality equipment.
The solution can be the professional TREND DVRs of 250 series. TREND 250X16 is a 16-channel DVR that provides recording capabilities of 4CIF (704 x 576) - in the maximum resolution provided by analog cameras. H.264 compression and compatibility with hard drives of capacity up to 2TB enable recording of very large amounts of video data. The images of 4 CIF resolution (704 x 576) can be recorded at frame rate of 6 fps in each channel, which allows to identify people, recognize license numbers etc.

An example of video surveillance system with remote functions

TREND 250X16 supports the most popular PTZ protocols. The DVR has the ability to define user accounts with varying degrees of power, which allows to limit management privileges and access rights for different groups of users.

The DVR provides maximum flexibility, including mobile monitoring. In addition to local access, the video preview can be obtained via Internet Explorer, the client software included with the DVR, and through mobile phones with Symbian or Windows Mobile OS. TREND 250X16 M72516 DVR is a really great choice for anyone expecting high quality at a reasonable price.

Video transmission over longer distances using twisted pair cable.

Video signal transmission via twisted-pair cable is justified not only economically (UTP cable is much cheaper than coaxial cable and has four twisted pairs), but also technically, due to elimination of interferences and possibility of using very long transmission lines , up to 2400 m. The general name of the device that matches (transforms) the 75 ohm impedance of an unbalanced source to the impedance of a balanced line formed e.g. by a pair of the UTP cable (and vice versa) is balun (balanced/unbalanced).

Transmitting a single video signal over a distance up to 400 m we can use one of the simple sets of passive baluns of Etrix series:

Transmitting several/many video signals over distances up to 400 m we can use a pair of the multi-channel passive baluns of Etrix series:

4-channel passive vdeo balun Etrix 4VP
M16662

Transmitting video signals over distances up to 2400 m we should use a pair of the following active baluns of Etrix series:

4-channel active video balun Etrix 4VA-T (transmitter)
M16744

We may combine any passive video baluns, whereas active devices have to be used in complementary pairs (of the same manufacturer and series; they are usually designed for distances over 500 m).
Active receivers can be sometimes used with passive transmitters over distances up to 1200 m.

CCTV monitoring - continuity of data transmission.

ACTi cameras of CAM-66XX series ( K1214, K1215, K1216) are equipped with two RJ-45 connectors - WAN and LAN. Aside from typical applications, this feature can be used for ensuring continuity of transmission in case of a connection loss. It is enough to activate "Failover" function in the camera's menu. Normally the transmission takes place through the WAN port, but when the connection is lost, the data is sent through the LAN port.

Normal operation

Link failure and activation of emergency operation

To create the links between the recording server and cameras located several hundred meters away we recommend to use wireless access points ULTIAIR N2301 and N2311. They have been specially designed to build efficient transmission networks for IP CCTV systems and ISP services.

Powerful Wi-Fi network with Internet access.

The router TP-Link TD-W8960N has been designed for sharing Internet connection provided by ADSL technology. It has built-in ADSL modem compatible with ADSL/ADSL2/ADSL2+ (Annex A), IEEE802.11n/b/g Access Point (transmission speed up to 300 Mb/s) and 4-port switch. The WAN port (RJ11) connects directly with telephone line.
The distinctive feature of TD-W8960N is support for 802.11n standard - capability of using data transfer speeds up to 300 Mb/s.
TD-W8960N ensures advanced access control and NAT, its DHCP server supports static assignment of IP addresses. The device also supports virtual servers, DMZ zone, remote logging and management. These functions are well supported by very fast and efficient processor. Additional advantages of the TD-W8960G router include easy configuration and management, performed via any Internet browser, as well as stable operation.

The devices are very well suited for building high-throughput Wi-Fi networks based on 802.11n standard, allowing wireless data exchange between computers at speeds up to 300 Mb/s (6 times faster than in the case of 802.11g devices). TP-LINK TD-W8960N routers are primarily used to build networks in homes and small offices.

Diagram of a WiFi network based on 802.11n devices

TRANS-DATA antennas - ideal solution for GSM/DCS/UMTS repeaters.

TRANS-DATA is a brand of high quality communication antennas. High quality materials and a very good performance of theses antennas guarantee very good and stable parameters.

Distinguishing features:

GSM/DCS/UMTS antenna TRANS-DATA KYZ8.2/9.5
A741030

The antennas are ideal for use with GSM/DCS/UMTS amplifiers/repeaters.
The A741030 antenna is a perfect choice for the outdoor antenna. In order to distribute the signal inside a room, we should employ the A741001 or A741002 antenna, each with 3 dBi gain and aesthetic appearance. To cover a long corridor, the best solution is to install the A741020 panel antenna on a suitable wall so that it radiates along the entire corridor.

Panel GSM/DSC/UMTS antenna TRANS-DATA KPV7.5/10
A741020

Czech (formerly Bohemia and Moravia). In the Czech Republic the UNESCO World Heritage Sites include: Prague, Brno, Czesky Krumlov, Holasovice, Kromeriz, Kutna Hora, Litomysl, Olomouc, Telc, Trebic, Zdar nad Sazavou and Lednice - Valtice.
The Renaissance urban complexes with castles, being true gems also due to their geographical locations, are Telc and one of the prettiest cities in the world - Czesky Krumlov.

Czesky Krumlov - an evening view of the castle

We have written about:

Bit Error Ratio (BER) - measurements. The picture quality in digital TV is solely dependent on the quality of the signal, in contrast to analog TV, where - with the decrease in signal level - noise becomes more visible. The image information obtained from a digital signal is unchanged as long as the decoder can identify errors and perform corrective procedures.
BER is the parameter determining overall possibility of reception and the quality of digitally transmitted programs...

BER measurement. A brief demonstration of the DVB-T signal meter Digiair PRO R10510

CCTV in a new supermarket chain. A new chain of stores under the name of Wellworths opened in March 2009. The new stores have been founded on the basis of Woolworths supermarkets. Offering a similar range of goods, they have to cope with a big problem, which is theft...

Diagram of the megapixel IP CCTV

Easier installation due to standard solutions - RACK cabinets. In everyday practice, 19" RACK standard for devices and dedicated RACK cabinets have been used for years now in telecommunications, IT systems, stage equipment, laboratories etc.
Aesthetic and functional RACK cabinets are designed for mounting all sorts of devices in standard 19" (482.6 mm) housings. The unit "U"- 1.75" (44.45 mm) allows to standardize the heights of the equipment mounted in the 19" RACK cabinets. The capacity of any RACK cabinet is given in the "U" units...

RACK cabinets and accessories


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