A Crash Course in Bluetooth Technology

In today’s world, electronics need to connect to one another everywhere you go – at home, at the office, in your car, the coffee shop, everywhere! The easiest, most secure and fastest connection available today is Bluetooth. You hear that word all the time, but what exactly is “Bluetooth?”

Bluetooth is an open/unlicensed wireless protocol that is used to exchange data over short distances from a wide variety of devices. Bluetooth was designed as an alternative to the RS232 wired data cable systems and it can connect several devices together without any problems with synchronization. Bluetooth capable devices can have a range from 30 feet to well over 100 feet depending on the device and version of Bluetooth.

Bluetooth devices use short radio waves to transmit the data using a technology called frequency-hopping spread spectrum which divides the data being sent and transmits each piece individually over (up to) 79 different frequencies. Bluetooth is such a versatile protocol and utilizing the technology you can connect and exchange information between cell phones, regular telephones, laptops, desktop computers, GPS systems, digital cameras, video game consoles, and more. Bluetooth makes it possible for all of these devices to communicate with one another when they are in range of one another – and best of all, since the devices use radio waves for communication, they do not require line-of-site to work properly.



Bluetooth has evolved out of several wireless technologies to become the new industry standard protocol. It is designed for low power consumption within a short range, but right now the prices vary widely for the technology depending on the application. Bluetooth devices also have the ability to maintain high levels of security even though the data is being transmitted wirelessly. The developers of the technology have put an emphasis on secure connections since the very beginning. Be aware though, that the manufacturer of the specific device that houses Bluetooth capabilities determines what level of security their specific device has.

Not surprisingly, Bluetooth has also moved into the security and surveillance arena where it is opening many new doors for camera systems and sensors.

~ The WTI Team



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WTI (Wireless Technology, Inc.)

Video Surveillance Products Dedicated to the Broadcast, Global Security and Transportation Markets!

www.gotowti.com ● www.wirelesstech.com

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LED Technology… Then, Now and Tomorrow.

LEDs or Light Emitting Diodes were first designed and built in the 1920s but were impractical for commercial use until 1962. Basically, when the diode inside of an LED is switched on the electrons are able to recombine and release energy in the form of a very bright light; this is called electroluminescence. The color of the light emitted is determined by the energy gap of the semiconductor in the LED. Early LEDs were only available in the color red but modern ones are available in any color across the visible spectrum, plus the ultraviolet and infrared wavelengths.

LEDs present many advantages over other light sources because they consume much less energy, they produce more light per watt than traditional lighting like incandescent bulbs, they have a much longer lifespan, they light up very quickly, they are brighter in intensity, they need no filters to emit specific colors as traditional bulb lighting does, they are not nearly as fragile as bulb lights are, and they are very small in size. LEDs also have very long life spans if they are kept in operation at low currents and low temperatures; most will last anywhere from 25,000 to 100,000 hours each.

LEDs have very few disadvantages but they do initially cost a bit more than conventional lights, they require a lower temperature environment to operate properly, and they are more sensitive to current/voltage fluctuations which therefore will need to be a bit more precise when utilizing LEDs.



LEDs can be used in many applications in many different industries, they are also a very environmentally friendly option because of their small size, low power usage and because they are completely non-toxic. They can replace traditional lighting like fluorescent bulbs; they are more practical for appliances such as televisions, radios, calculators and watches. Companies now make super-bright flashlights with LEDs. Since the LED is completely sealed they are perfect for outdoor signage since the elements will not affect their operation so they are now used for highway signs, construction, advertisements and they are even now being used to replace and upgrade traffic lights for better visibility.

Recently there have been some amazing advancements in LED technology… there has been talk that LEDs will be used for new strip-style lights to replace fluorescent bulbs in office environments that will also have the capability to interact directly with your computer providing your connection to the internet. No wires, no fuss.

WTI utilizes high-technology enhanced power LEDs in all of our infrared camera systems, like the Ambervision series for example. For more information check out the product page at http://www.gotowti.com/Products_Ambervision.htm or to view our entire line of solutions please visit http://www.gotowti.com.


~The WTI Team



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WTI (Wireless Technology, Inc.)

Video Surveillance Products Dedicated to the Broadcast, Global Security and Transportation Markets!

www.gotowti.com ● www.wirelesstech.com

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Check out WTI’s new state-of-the-art SMT PCB assembly machine!

Understanding and successfully addressing each of our customer’s needs is the overriding mission that drives WTI (Wireless Technology, Inc.) and the business relationships we have with our customers. We realize that each customer has unique needs, however after 25 years of serving our customers we find there are three “interwoven-threads” that our customers have come to rely on from WTI. They are: Product Performance, Product Quality, and Cost of Ownership. Keeping all of these “interwoven-threads” equally strong requires constant customer feedback, vigilance in Research and Development, investing in manufacturing technology and of course the all important cost of ownership.

In this vein, WTI is very proud to announce that we have chosen the Juki Corporation and their high-speed SMT placement equipment to replace and upgrade our current SMT line. This allows WTI to meet its need for a wide variety of in-house manufacturing applications with the highest performance possible. The new Juki KE-2080 is a high-speed, high-accuracy component centering SMT machine that uses unique laser technology and extremely powerful vision processing to ensure correct and exact placement every time!

~Dan Fancher, President/C.E.O.

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WTI (Wireless Technology, Inc.)

Video Surveillance Products Dedicated to the Broadcast, Global Security and Transportation Markets!

www.gotowti.com ● www.wirelesstech.com

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Far, Far Away…

One of the most frequently asked questions that we receive about our products is “How far can the camera see?” The answer to this question is not the same for every application, so the correct answer depends on who is asking the question.

In a highway traffic application, for example, the customer might want to know how far down the freeway the camera can look and display several lanes of traffic across the video image. In another type of vehicle tracking application, the customer might want to know at what distance the camera is able to resolve license plate numbers.

Let’s consider the highway traffic application first. The Interstate Highway System uses a standard lane width of 12 feet, so we will base our viewing distances on this figure. If we know what the horizontal field of view of the camera is at its maximum zoom setting, we can easily calculate at what distance the video image will show 1, 2, 3 or 4 lanes of traffic to the traffic engineer at the operations center. Here is a table showing the maximum viewing distances for cameras with several different zoom factors and horizontal field of view values:

Normally, a traffic engineer would be interested in the inbound traffic in the morning and the outbound traffic at night, so on an 8 lane major thoroughfare, we would use a 4 lane width for calculating the camera viewing distance. We can see from this table that if a traffic engineer was asking “How far can this camera see?”, the answer would probably be about 0.3 Miles for the camera with the x35 zoom capability. With this information, the engineer would be able to determine how far apart the cameras could be placed alongside the highway in order to have adequate coverage for good viewing quality. If these were pan, tilt and zoom cameras capable of looking in either direction down the highway, the cameras could be placed 0.6 miles apart.

Another vehicle related application that depends on knowing how far the camera can see is license plate recognition. Determining the maximum distance at which a license plate can be read is a little more complicated than the straight-forward calculation used in the previous highway application, though. The maximum usable distance in this application will depend on whether the intent is for an operator to be able to read the license plate or if the license plate is going to be read by an automated Optical Character Recognition (OCR), computer based system.

OCR license plate readers are highly sophisticated machine vision systems that usually use special cameras with built in high powered infrared LED strobe lights to enable optimum viewing in all lighting conditions. They also are typically used in situations where the vehicle position and orientation is carefully controlled, like a community guard gate or a toll booth lane. These types of systems usually are specified to operate at distances of about 10 feet to 40 feet.

In the case of conventional color cameras being viewed by an operator during daylight conditions, though (say on a street or highway), we can make some assumptions and come up with a ballpark figure as a guide for how close a vehicle must be for an operator to read the license plate. This might be a situation where a guard is monitoring an entire parking lot with a pan, tilt and zoom camera, and wants to zoom in on the vehicle entering the gate occasionally, and write down the license plate number. In the JPEG image below, which has a 512 x 384 pixel resolution, the vehicle fills up the middle third of the video image, and the license plate number is discernable under these relatively optimal lighting conditions. A resolution of 500 lines of resolution would be about the upper limit under ideal installation conditions for a high quality CCD camera.

The license plate actually encompasses about 81 x 43 pixels in this image. The image below shows the license plate section blown up in size to show the actual resolution of the license plate portion of the image.

As you can see, the license plate number, even at a resolution of only 45 x 23 pixels or so is still just barely discernable by a human operator under good lighting conditions (if you squint a bit). This would probably be the minimum resolution that would work. If we calculate the maximum vehicle distance using the same cameras as before and using the size of the license plate as a guide we get approximately the same results that we did for the one lane calculations.

Naturally this application depends on a lot of variables, like the lighting conditions, the quality and distance of the video cabling, the cleanliness of the license plate, the operator skill and other factors. These numbers are only a very rough guideline. Your results may vary.

So, when considering different applications, the answer to the question “How far can the camera see?” is, “it depends”.

~Dale Roche, Director of Engineering

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WTI (Wireless Technology, Inc.)

Video Surveillance Products Dedicated to the Broadcast, Global Security and Transportation Markets!

www.gotowti.com ● www.wirelesstech.com

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