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DIPOL Weekly Review - TV and SAT TV, CCTV, WLAN
No. 41/2009 (Dec. 7, 2009)
LTE - the technology of the future. LTE (Long Term Evolution) is a technology of mobile networks in which the download speed will reach up to 326 Mb/s and upload speed up to 86 Mb/s (20 MHz channel, 64QAM modulation, 4x4 MIMO).
The technology is seen as the next stage in the development of mobile networks, allowing them to achieve the possibility of efficient multimedia transmission. The popularity of smartphones (like iPhone) means the growing demand for mobile broadband networks.
LTE technology is flexible, both in terms of frequency band and width of the transmission channel. Depending on the needs, LTE networks can operate at frequencies from 700 MHz (rural areas - higher ranges) to 2.6 GHz (metropolitan areas). It is possible to use transmission channels with the following bandwidths: 1.4 MHz, 3 MHz, 5 MHz, 10 MHz, 15 MHz, and 20 MHz. With the increase in channel width, the link speed rises as well.
The "downlinks" use OFDM spread spectrum technique with multiple subcarriers, whereas the "uplinks" are based on SC-FDMA (Single Carrier Frequency-Division Multiple Access) that uses a single carrier (to save the battery life of the client device) .
Additionally, LTE uses Multiple Input Multiple Output (MIMO) technology which utilizes many antennas. So far, client terminals are usually equipped with two antennas (MIMO 2x2), due to implementation problems in such small devices.
An important element of LTE is a new network structure, called System Architecture Evolution (SAE). It is based entirely on IP protocol.
The technology is evolving in two directions: FD-LTE and TD-LTE. They differ in the utilization of the channel. In the case of FD-LTE, the transmission channel is divided into two frequency bands - one of them is used for transmission towards the base station and the second from the base station to the terminal.
The TD-LTE uplink and downlink transmissions are spread over the whole channel. The time at which transmission is carried out is divided into time slots, separated by guard time. In each time slot the transmission goes only one way. This allows for flexible use of the capacity of the transmission channel.
Currently, TD-LTE is gaining more and more supporters; not without significance is the fact that it is chosen as the primary technology for building commercial LTE networks in China.
The first commercial LTE networks will be launched in 2010 (China, USA, Scandinavia, Japan), however, works are already carried out to develop a more advanced version of this technology, namely LTE-A (Advanced), with estimated throughput of 1 Gb/s (downlink) and 500 Mb/s (uplink) within a 100 MHz band.
Already in May, China Mobile will launch a pilot TD - LTE network at the Expo 2010 in Shanghai
Near the equator, but where? Geostationary orbit is located over the equator. Telecommunications satellites deployed on the orbit can keep communication with terrestrial stations without a need of changing the direction of antennas. Geostationary orbit is a circular orbit and runs just 42160 km from the center of the Earth, in the place where the gravity force is balanced by the centrifugal force.
The consequence of this is necessity of different elevation angles of the terrestrial stations, depending on the latitude. In the following pictures the elevation angles amount to 90 degrees.
So it means they are located close to the equator, but where? The answer at the end of this issue.
Close to the equator, but where? - See at the end of this issue.
(Photo by J. Babula)
RF amplifiers for digital and analog TV signals - Cabrio Line. TERRA company has launched a new series of distribution (building/house) amplifiers. The HA-129 R82314 (47-862 MHz), HA-129R30 R82315 (47-862 MHz), and HA-129R65 R82316 (87-862 MHz) amplifiers from the Cabrio Line have been designed for amplification of terrestrial TV signals, both analog and digital broadcasts.
The HA-129R30 R82315 and HA-129R65 R82316 amplifiers have been equipped with return channels, 5-30 MHz and 5-65 MHz respectively. An important advantage is active return channel, used for the first time in such a category of amplifiers. It allows to transmit the signal over longer distances. A new feature is also the switch changing the range of maximum gain, from 24-27 dB to 32-36 dB, which combined with 17 dB gain adjustment allows for precise changes of amplification in a wide range. The amplifiers are to be used inside buildings. They have built-in power supplies. The -30 dB test connectors allow to measure also return signals.
- The amplifiers of HA-129 series offer built-in cable equalization to help compensate for cable losses both in forward and return path. They can change the level of the signal depending on the frequency of the amplified channel.
- Maximum CTB/CSO output level (EN50083-3) of the forward signal is 100 dBuV.
- Gain of return channel: 18-21 dB, with 15 dB adjustment.
- Maximum output level IMD3=60 dB (DIN45004B): 114 dBuV.
- Return loss at 40 MHz above 14 dB (-1.5 dB/octave, at least 10 dB), noise figure 8.5 (forward path) and 6 dB (return path).
Building Amplifier: Terra HA-129
HA129 amplifier
R82314
New line of Opticum LNBs. DIPOL now offers satellite Opticum LNBs from "Premium" line, for very competitive prices. They feature solid construction and good performance including exceptionally low noise figure - 0.1 dB.
TWIN LNB: Opticum/Orton LTP-04H Premium 0.1dB
TWIN MONOBLOCK LNB: Opticum/Orton LMTP-04H Premium 0.1dB
Opticum TWIN LNB
A9842
Opticum MONOBLOCK TWIN LNB
A9846
CodeNameApplication
A9842LTP-04HTwin - 2 receivers (or 1 PVR with dual tuner)
A9844LQP-04HQuad - 4 receivers (or 2 PVRs with dual tuners)
A9845LMP-04HMonoblock - Hotbird and Astra, 1 receiver
A9846LMTP-04HTwin Monoblock - Hotbird and Astra, 2 receivers
A9847LMQP-04HQuad Monoblock - Hotbird and Astra, 4 receivers
Combination of elegance and performance - 400 GB HDD for receivers with PVR function. The external hard drive OPTICUM A99400 is dedicated for use with satellite, cable, and terrestrial receivers heaving PVR function (DVB-S/S2, DVB-T or DVB-C receivers).
Its 400 GB capacity allows to record several tens of hours of High Definition material. The device has elegant, slim design (black, aluminum housing and leather case) that will enhance the look of any receiving set.
External Hard Drive: OPTICUM 2.5
OPTICUM 2.5" 400GB/USB2.0 HDD
A99400
The hard drive is equipped with USB cable used for data transmission and power supply. One can employ an external 5 VDC power supply in case of cooperation with a receiver limiting USB current capacity below the needs of the hard drive. The HDD cooperates very well with Opticum and Ferguson receivers.
The HDD is a universal device, so it can successfully serve as a portable data and multimedia storage for PCs or modern televisions. A great advantage of the device is high speed and quiet operation.
CCTV in prisons. The SN-FXP3200MIR M10790 camera meets all requirements for cameras listed in the Regulation of the Minister of Justice, issued on October 16, 2009 in Poland. The regulation specifies the types of equipment and technical means used for transmitting, reproducing and recording images and/or sound in prisons.
High-resolution video (550 TVL), built-in IR illuminator, changeable focal length (2.8-11 mm), motion detection, possibility of programming up to 8 privacy zones - are the main features of this advanced model. The ability to set privacy zones is indispensable in monitoring of cells (to exclude sanitary fittings and baths from the observation area - the camera is compliant with adequate IP class - IP66).
Motion detection is particularly useful for monitoring of convicted persons - in the case of detecting any movement in the defined area the operator is instantly informed.
View of the SN-FXP3200MIR M10790 camera
installed in one of prisons in Malopolska, Poland
Online monitoring of construction site. S.M. Invest - the company preparing and carrying out building investments and responsible for property management - sought a way to provide its customers with possibility to watch the progress of construction works.
The task has been undertaken by Zax.pl - ISP and VoIP provider as well as hosting, CCTV and IP CCTV company. The installation uses outdoor megapixel IP camera ACTi ACM-1231 (K1511) and wireless link. The implemented website allows to preview the image using any web browser. Proper operation requires Java software and at least 2 Mbps of bandwidth. The customers can observe the ongoing construction works.

Online view of the site
Outdoor Megapixel IP Camera: ACTi ACM-1231
Zax.pl decided to use for online monitoring
the most popular ACTi camera - ACM-1231 K1511
The author gets "Chameleon mug".

We encourage installation companies to describe implemented systems.
How to get the "Chameleon mug"?
New features of ACTi cameras - GOP setting. IP CCTV market leader - ACTi company - gradually modernizes its products. The latest achievement is the firmware for all ACM cameras, ver. 3.11.13. It introduces GOP (group of pictures) control. GOP structure specifies the order in the group of successive frames within a coded video stream. The control decides on the number of I-frames in the group (I-frames are reference images representing fixed images in relevant moments that allow to reconstruct complete images). Other frames between I-frames (P and optionally B, D) transmit only information on the changes in the images. Therefore, control of the GOP is crucial to save bandwidth when monitoring still scenes.
In connection with "Event handler", the software allows to create a formula that, in the case of increased motion in the image, shortens the GOP (increasing the ratio of I-frames to the rest of the frames). It results in improved quality of motion images, whereas only small amounts of data are transmitted when nothing happens in the monitored area. The dependence of the GOP size from the frequency of the I-frames is shown below.
The 3.11.11 version described 3 weeks ago with revolutionary "Event handler" has been enriched with this important function for optimizing use of network resources.
GOP structure at 5 fps in various dynamic conditions
Power over Ethernet (PoE) adapter. The PoE adapter N9206 allows to power LAN devices through typical transmission cable (FTP/UTP etc.) - diagram 1.
It is very useful solution in the case of Access Points, where the AP can be placed in a hermetic box just by the antenna (to lower the loss in the RF cable) and supplied via transmission cable from power source located inside a building.
The adapter can cooperate with all devices compliant with 802.3af (PoE) standard, e.g. IP cameras from ACTi. There are devices which should be powered via Ethernet (RJ-45) port with voltages different from 48 VDC. The example is ULTIAIR family (10-28 VDC). The devices should be connected according to the diagram 1, but in each case the supplying voltage has to be compliant with the relevant specifications.
Devices that cannot be powered via Ethernet port should be connected according to the diagram 2.
How to power devices
compliant with PoE 802.3af

Diagram 1
How to power devices
not compliant with PoE 802.3af

Diagram 2
Sultanate of Brunei. The official name - the State of Brunei Darussalam - the Abode of Peace. It is a country located on the north coast of the island of Borneo, in Southeast Asia. Apart from its coastline with the South China Sea, it is completely surrounded by Malaysia and separated into two parts.
The northern part of the country is lowland, in the south of the smaller part (Temburong) there are mountains with the country's highest peak (Pagonprick, 1850 m above see level). The East coast is a marshy bank, the rest is sandy. The country has a cool equatorial climate, also known as a tropical rain forest climate (75% of Brunei is covered by equatorial forests). The Sultanate of Brunei has 1150 km of roads (399 km of asphalt roads) and 13 km of railways.
His Majesty Paduka Seri Baginda Sultan Haji Hassanal Bolkiah Mu'izzaddin Waddaulah is the head of state with full executive authority. During his reign he amassed a private fortune estimated at many billion dollars (Forbes World's Richest People, 1997 - the richest man in the world - $38 billion, just before William Gates - $36.4 billion).
(Wikipedia, Forbes)

Mosque in Bandar Seri Begawan,
the capital of the Sultanate of Brunei
We have written about:

Mast amplifier - a good remedy for low signal. In difficult reception conditions (levels of antenna signal below 50 dB) it is far better to use mast amplifier than antenna diplexer and apartment amplifier, because the signal is not additionally attenuated by the distributing cable that would decrease S / N ratio...
- archive DWR of May 25, 2009

Compact IP camera - PiXORD P428 - easy monitoring of building sites, storage yards and warehouses, parking lots. IP camera PiXORD P428 (K1136) is fixed outdoor camera designed for all-year-round operation. The camera module (with detachable lens) has been placed in watertight IP66-rated aluminum housing equipped with 230VAC/12VDC adapter, heater and fan. The latter elements ensure reliable operation even in extreme weather conditions - they switch on and off automatically to maintain proper internal temperature...
- archive DWR of Jan. 19, 2009

Wireless link with an intermediate point. In many situations it is impossible to achieve a direct link between the locations that should be connected. However, lack of mutual visibility does not eliminate wireless technology. In most cases the solution is to create an intermediate node...
- archive DWR of March 16, 2009

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