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

New augmented reality service from Google.

This year's Google I/O Developer Conference was full of information about the current Google projects. Many of them use augmented reality systems, machine learning and AI technologies. One of the most interesting projects announced by Google CEO Sundar Pichai is Google Lens service. Google Lens can use the phone's camera to identify objects around and give the user more information about them or even suggest or perform some related actions. During the conference, some details were given on this project. The service will be available through Google Assistant and Google Photos. For example, directing the phone's camera to a flower, the user will get its name and description, or when walking down a street and capturing the name or logo of a restaurant, the user will get detailed information about it along with customers' opinions. Google Lens also integrates character and meaning recognition systems. After capturing the image of a router's sticker with the password, it can automatically setup connection with it, or viewing the menu card in a restaurant, it can can automatically translate it into the user's mother tongue. Google Lens will also make it easier for users to buy any products - by capturing an ad for a concert, the user will be offered the ticket and the event will be added to the calendar on the phone. The contextual menus may be personalized according to the user's preferences.

Google Lens in action at Google I/O Developer Conference 2017.
From left to right: recognition of objects, places, printed information (along with automatic configuration)

Android has already passed 2 billion active devices. The system is very popular due to well-developed services. The current trends include the recognition of voice, text and image, and processing the data to extract useful information. The accuracy of image recognition algorithms seems to exceed the ability of the human being. This level has been achieved through machine learning techniques and neural networks. According to Google's announcement, the augmented reality on smartphone screens is expected to be available shortly - we are looking forward to exploit the potential of the system.

Signal LCD mounts.

The selection of a suitable mount must be based on the required load capacity, mounting standard, and screen size. The most important parameter is the load capacity, which has to be at least the same as the weight of the TV/monitor (a safety margin is highly recommended). This issue is basic for the security of the display and the viewers.

Each of the mounts presented in the following table can be adjusted horizontally, i.e. the TV can be rotated around its vertical axis. However, due to the construction and design, cheaper solutions are intended for use in fixed positions, without frequent changes of them. Adjustments on a daily basis can cause instability, usually leaning to the left or right. Customers who want to change the position of their televisions frequently, e.g. depending on whether they watch them sitting by the table or lying on the sofa, they should choose the LPA16-444A E93160 or LPA19-442 E93168 models. The structures of the mounts ensure suitable rigidity and the bearing bushes allow for easy and frequent adjustments of the TV position, meeting the requirements of even the most demanding customers.

Four-system security cameras.

n-cam and v-cam cameras are universal devices for applications in modern CCTV systems based on various types of DVRs. The video system is selected with the stick placed in the small box on the camera cable during the initial 5-second period, just by long pressing (5 s) the thumb stick to the right (HD-TVI), left (CVBS), up (AHD), or down (HD-CVI).

View of the control box on the connection cables of n-cam and v-cam cameras.
With the thumb stick the user can select the required video system.

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 provide Channel-zero Encoding option. With this function, the user can preview images from 16 channels in one window of a web 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:

Channel-zero Encoding window in a web browser

Splicing of optical fibers - preparation of fiber ends.

Regardless of the choice of a welding/splicing machine, the fusion splicing process is quite similar, with a series of steps. The first of them is the removal of the fiber coating, 250 μm or sometimes 900 μm. Independently from the type of the spliced fibers, the bare cladding has diameter of 125 μm, the size needed for further operations. Then, it is necessary to clean the fibers with isopropyl alcohol (normally with dust-free wipes or cotton swabs), and cleave them using a suitable cleaver. The latter operation is very critical - it is important to ensure both the appropriate length of the fiber ends (in most cases the installer does not have anything to measure, because the construction of the cleaver allows for easy selection of the suitable length) and perfect angles of the cleavage planes. In practice, splicers accept some deviation from the right angle (about 1 degree), but more precise cleaving will result in better performance of the fusion splices. Low quality cleaver or insufficient accuracy of this operation are the main reasons of lower quality of the splices.

Fiber cleaving. The fiber scraps have to be put into dedicated trash can for utilization.

After placing the fibers in the welding machine, the results of the previous operations are verified. In the case of an excessive dirt on a fiber end face or improper cleaving, the device will notify the user to repeat the fiber end preparation process. When everything is in order, the fibers are welded with the use of an electrical arc, and the fusion splice is tested for strength and transmission parameters (loss).

The process of joining fibers usually takes several to about ten seconds. The next and last step is the protection of the splice with a heat-shrinkable sleeve, with the use of a heat oven, which is often integrated with the fusion splicer. Newly made splices are fragile and always require additional protection. Heat-shrinkable sleeves protect them mechanically and allow for easy placement of the connected fibers in splice cassettes.

RF connectors in LTE modems.

The user of a wireless network device such as access point, wireless adapter, modem etc. who wants to buy an external antenna should know the type of the antenna connector used in the device. A multitude of solutions and slight differences in appearance mean that less experienced users can have great difficulty in choosing the antenna with a matching connector.

The type of the connector depends on the device manufacturer and may differ in the case of devices operating in different frequency bands. The most popular RF connector used in LTE modems/routers is SMA.

Typically, the antenna cable should be terminated with SMA plug

The included cables coming out from each of the two ATK-LOG ALP LTE MIMO 2x2 A7054_5 antenna units are 5 m long and are terminated with SMA plug

WDM (single-fiber) vs. duplex (two-fiber) links. Installers can choose solutions based on Wave Division Multiplexing (WDM), which require only one fiber for bidirectional data transmission or those with two fibers (duplex). Choosing a solution, they usually take into consideration its cost and the number of fibers available in the cable. However, there is one more technical aspect associated with the use of one or two wavelengths... >>>more

A graph showing the dependence of the attenuation on the wavelength in the case of:
microbends (blue), macrobends with 20 mm (red) and 25 mm radius (green)
(The data come from studies of Cabelcon company)

PTZ camera N-CAM 870 (HD-TVI / AHD / HD-CVI)