RTS Wireless Network Discussion

Monaco Telecom has revealed it is working with wireless broadband solutions provider Alvarion Ltd (Nasdaq:ALVR), networking solutions provider Cisco and mobile communications company Nokia (NYSE:NOK), to set up a Center of Excellence on Mobile Worldwide Interoperability for Microwave Access (WiMAX) in Monaco.

SOMA Networks Inc (SOMA) announced it has been selected by Bharat Sanchar Nigam Ltd (BSNL), India’s state-owned telecomms company, to deploy a Mobile WiMAX network in India, following field trials in urban, suburban and rural areas.

Trango Broadband Wireless announced an exciting new line-up of broadband wireless product releases in both licensed and unlicensed spectrums for 2008 as the company continues to execute on its new strategic direction and focus. Trango Broadband, already a leader in unlicensed band wireless solutions offerings for many years, will build on its decade of experience in the RF space to continue its expansion into the licensed band wireless solutions arena.

In its recently released study covering the entire commercial satellite transponder leasing sector, NSR projects that worldwide carriage of new standard definition (SD) and high definition (HD) channels for all categories of television services will account for between 75% and 85% of C- and Ku-band transponder demand growth in most regions around the world.

Harris Stratex Networks, Inc. (Nasdaq: HSTX) announced that iZZinet Sdn Bhd, Malaysia’s iBurst operator, has selected Harris Stratex’ Eclipse radios for its nationwide wireless broadband network roll-out program.

With the recent approval of Long Term Evolution (LTE) technology specifications by the leading global wireless standards organization 3GPP, LTE is on target and continuing its momentum as the next phase of technology development for the GSM family of technologies, according to industry association 3G Americas.

NEC Corporation announced that it has been named the world’s leading microwave communication-system company by industry analysts. NEC ranked No.1 in the third quarter of CY2007 with a total global share of 31%. The period is the first in which NEC earned the leading position, which can mainly be attributed to robust sales in Asia and the Middle East accompanying the expansion of mobile phone markets overseas.

Strix Systems announced the introduction of the company’s highest-powered, highest performance Mobile Wireless System (MWS) 100 to its award winning Access/One product line. The MWS is one of the industry’s highest performance mobile extension which enables on-board video surveillance, voice over IP and critical data applications for in-vehicle wired or wireless client connectivity in public safety, railway, municipal, strategic and tactical wireless broadband mesh networks.

Airband Communications, Inc. announced expanded coverage and capacity of its high-bandwidth solutions in Houston. As part of its national expansion strategy, the company has increased its market reach and service area in the Houston market by 50 percent. The expansion also includes a doubling of Airband’s network capacity driven by local customer demands for higher bandwidth services.

Research and Markets has announced the addition of WiMAX Comprehensive Business Planning Package to their offering. The comprehensive WiMAX package includes the Mind Commerce WiMAX Business Plan, WiMAX Business Planning Tool, and WiMAX RFP. This represents the most comprehensive WiMAX business planning kit available today as it provides a business plan, planning tool with working spreadsheet, and RFP. Each of these are also available separately.

Just in case you are looking for a source of information on the FCC’s ongoing auction of the 700MHz, we have collected some information and published it for your reading pleasure.

Cisco (NASDAQ: CSCO) and the Oriental Bangkok Hotel announced the world’s first deployment of Cisco’s next-generation wireless 802.11n technology in the hospitality industry. The new high-speed wireless network supports the Oriental Bangkok’s vision to offer superior guest experience through information and communications technology (ICT).

A contract to deliver a complete carrier VoIP solution to provide a residential VoIP service to the US customers of Clearwire, a provider of portable and reliable wireless high-speed Internet service, has been signed by communications solutions provider Nortel (NYSE:NT) (TSX:NT).

WiChorus and Aptilo Networks announced that they have completed interoperability testing (IOT) of WiChorus’ Intelligent ASN Gateway with Aptilo’s WiMAX CSN (Connectivity Service Network) System, the market’s first integrated solution for standards-compliant Mobile WiMAX AAA and Service Control. Testing of the WiChorus and Aptilo products was based on the WiMAX Forum’s NWG 1.0.0 specification.

One Ring Networks announced that it has chosen Redline Communications Group Inc. to deliver its WiMAX-based services. Redline Communications Group Inc. (TSX: RDL) (AIM: RDL) is a leading provider of standards-based WiMAX access and broadband wireless infrastructure products. Redline will be supplying One Ring with their 3.65 GHz RedMAX products to complement the company’s new service offerings as a result of their newly released WiMAX network.

Mikrotik are announcing their new RouterBOARD model - the RB/333! It is based on PowerPC E300 CPU + QUICC Engine Coprocessor, it’s 2-3 times faster than the current high-end model RB/532 of Mikrotik. Unit is equipped with three LAN ports and three miniPCI slots, that can support three high-power R52H 802.11a/b/g (~350mW) cards without any problems. RB/333 is ideal for high-load routing tasks, and optimized for Dual Nstreme. Listed price on their website for a unit is $180, including RouterOS Level 4 license. Wireless AP is supported.

Setting up wireless devices that belong to the 802.11 family is relatively simple, but you do have to pay attention to a few simple factors.

Ad-hoc or infrastructure mode?
The 802.11 wireless standards support two basic configurations: ad-hoc mode and infrastructure mode.

In ad-hoc mode, wireless user devices such as laptop computers and PDAs communicate directly with each other in a peer-to-peer manner without the benefit of access points.

Ad-hoc mode is generally used to form very small spontaneous networks. For instance, with ad-hoc mode, laptop users in a meeting can quickly establish a small network to share files.

Infrastructure mode uses wireless access points to enable wireless devices to communicate with each other and with your wired network. Most networks use infrastructure mode.

The basic components of infrastructure mode networks include:

The radios embedded or installed within the wireless devices themselves. Many notebook computers and other Wi-Fi-compliant mobile devices, such as PDAs, come with the transmitters built in. But for others, you need to install a card-type device to enable wireless communications. Desktop PCs may also need an ISA or a PCI bus adapter to enable the cards to work.
The access point, which acts as a base station that relays signals between the 802.11 devices.
One or many access points?
Access points are standalone hardware devices that provide a central point of communication for your wireless users. How many you need in your application depends on the number of users and the amount of bandwidth required by each user. Bandwidth is shared, so if your network has many users who routinely send data-heavy multimedia files, additional access points may be required to accommodate the demand.

A small-office network with fewer than 15 users may need just 1 access point. Larger networks require multiple points. If the hardware supports it, you can overlap coverage areas to allow users to roam between cells without any break in network coverage. A user’s wireless device picks up a signal beacon from the strongest access point to maintain seamless coverage.

How many access points to use also depends on your operating environment and the required range. Radio propagation can be affected by walls and electrical interference that can cause signal reflection and fading. If you’re linking mobile users indoors-where walls and other obstructions impede the radiated signal-the typical maximum range is 150 feet. Outdoors, you can get greater WLAN range-up to 2000 feet (depending on your antenna type) where there’s a clear line of sight!

For optimal speed and range, install your wireless access point several feet above the floor or ground and away from metal equipment or large appliances that may emit interference.

Battle of the bands.
In addition to sharing bandwidth, users also share a band. Most IEEE 802.11 or 802.11b devices function in the 2.4-2.4835-GHz band. But these frequencies are often congested, so you may want to use devices that take advantage of the IEEE 802.11a 5.725-5.825-GHz band.

No matter what frequency you use, you’ll want to isolate your users from outsiders using the same frequency. To do this, assign your users a network identifier, such as an Extended Service Set Identifier (ESSID), as well as distinct channels.

Web and wired network links.
The access point links your wireless network to your wired network, enabling your wireless users to access shared data resources and devices across your LAN enterprise. Some access points even feature capabilities for routing traffic in one or both directions between a wired and wireless network.

For Internet access, connect a broadband router with an access point to an Internet connection over a broadband service such as DSL, cable modem, or satellite.

For connecting network printers, you can dedicate a computer to act as a print server or add a wireless print server device; this enables those on your wireless network to share printers.

When to use external antennas.
If you plan to install access points, you can boost your signal considerably by adding external antennas. Various mounting configurations and high- and low-gain options are available.

You can also use add-on antennas to connect nodes where the topology doesn’t allow for a clear signal between access points. Or use them to link multiple LANs located far apart.

Additional external antennas are also useful to help overcome the effects of multipath propagation in which a signal takes different paths and confuses the receiver. It’s also helpful to deploy antennas that propagate the signal in a way that fits the environment. For instance, for a long, narrow corridor, use an antenna that focuses the RF pattern in one direction instead of one that radiates the signal in all directions.

Plan ahead with a site survey.
A site survey done ahead of time to plot where the signal is the strongest can help you identify problem areas and avoid dead spots where coverage isn’t up to par or is unreliable. For this, building blueprints are helpful in revealing potential obstructions that you might not see in your physical site walkthrough.

To field test for a clear signal path, attach an antenna to an access point or laptop acting as the transmitter at one end. Attach another antenna to a wireless device acting as a receiver at the other end. Then check for interference using RF test equipment (such as a wireless spectrum analyzer) and determine whether vertical or horizontal polarization will work best.

Isotropic Antenna. First, think of the introduction to the old RKO movies. A huge tower sits on top of the world and emanates circular waves in all directions. If you could actually see the waves, they would form a perfect sphere around the tower. This type of antenna is called an isotropic antenna, and does not exist in the real world. It is theoretical and is used as a base point for measuring actual antennas.

Now let’s turn to real-world antennas. There are many types of antennas that emit radio waves in different directions, shapes, and on different planes. Think of the spherical isotropic antenna. If squeezed from the sides, it will become shaped like a wheel and will concentrate waves on a vertical plane. If squeezed from the top, it will flatten out like a pancake and radiate waves on a horizontal plane. Thus, there are two basic types of antennas: directional and omnidirectional.

Directional antennas. Directional antennas, primarily used in point-to-point networks, concentrate the waves in one direction much like a flashlight concentrates light in a narrow beam. Directional antennas include backfire, Yagi, dish, panel, and sector.

Backfire. This small directional antenna looks like a cake pan with a tin can in the middle. It’s designed to be compact, often under 11" in diameter, making it unobtrusive and practical for outdoor use. These antennas also offer excellent gain, and can be used in both point-to-point or point-to-multipoint systems.

Yagi. The Yagi-Uda (or Yagi) antenna is named for its Japanese inventors. The antenna was originally intended for radio use and is now frequently used in 802.11 wireless systems. A Yagi antenna is highly directional. It looks like a long fishbone with a central spine and perpendicular rods or discs at specified intervals. Yagi antennas offer superior gain and highly vertical directionality. The longer the Yagi, the more focused its radiation is. Many outdoor Yagi antennas are covered in PVC so you can’t see the inner structure. Yagi antennas are good for making point-to-point links in long narrow areas (for instance, connecting to a distant point in a valley) or for point-to-point links between buildings. They can also be used to extend the range of a point-to-multipoint network.

Parabolic or Dish?. These antennas look like a circular or rectangular concave bowl or "dish". The backboard can be solid or a grid design. Parabolic grid designs are excellent for outdoor use since the wind blows right through them. The concave nature of this dish design focuses energy into a narrow beam that can travel long distances, even up to several miles. This makes parabolic antennas ideal for point-to-point network connections. Since they generate a narrow beam in both the horizontal and vertical planes, offer excellent gain, and minimize interference, they’re ideal for long-distance point-to-point networks.

Panel or Patch? These antennas are often square or rectangular, and they’re frequently hung on walls. They’re designed to radiate horizontally forward and to the side, but not behind them. Sometimes they’re called "picture-frame" antennas.

Panel antennas are ideal in applications where the access point is at one end of a building. They’re good for penetrating a single floor of a building, and for small and medium-size homes and offices. Since they might not have much vertical radiation, they might not be a good choice for multifloor applications. Because panel antennas can be easily concealed, they’re a good choice when aesthetics are important.

Sector. A sector antenna can be any type of antenna that directs the radio waves in a specific area. They are often large, outdoor flat-panel or dish-type antennas mounted up high and tilted downward toward the ground. These antennas are often used in sprawling campus settings to cover large areas.

Omnidirectional antennas. Omnidirectional antennas provide the widest coverage possible and are generally used in point-to-multipoint networks. Their range can be extended by overlapping circles of coverage from multiple access points. Most omnidirectional antennas emanate waves in a fan-shaped pattern on a horizontal plane. Overall, omnidirectional antennas have lower gain than directional antennas. Examples of omnidirectional antennas include: integrated, blade, and ceiling.

Integrated. Integrated antennas are antennas that are built into wireless networking devices. They may be embedded in PC card client adapters or in the covers or body of laptops or other devices, such as access points. Integrated antennas often do not offer the same reception as external antennas and might not pick up weak signals. Access points with integral antennas must often be moved or tilted to get the best reception.

Blade. These small, omnidirectional antennas are often housed in long, thin envelopes of plastic. They are most often used to pick up a signal in a low-signal or no-signal spot. You usually will see them on the walls of cubicles, mounted on desktops, or even hung above cubicles to catch signals. They’re basically an inexpensive signal booster.

Ceiling Dome. These are sometimes also called ceiling blister antennas. They look somewhat like a smoke detector and are designed for unobtrusive use in ceilings, particularly drop ceilings. Ceiling dome antennas often have a pigtail for easy connection to access points. They’re excellent for use in corporate environments where wide coverage over a cube farm is needed.

Wave basics. To better understand wireless antennas and networking, there are some basic measurements and terms that need to be discussed.

Gain. One of the primary measurements of antennas is gain. Gain is measured as dBi, which is how much the antenna increases the transmitter’s power compared to the theoretical isotropic antenna, which has a gain of 0 dBi. dBi is the true gain the antenna provides to the transmitter’s output. Gain is also reciprocal-it’s the same transmitting and receiving. Higher gain means stronger sent and received signals. An easy way to remember gain basics is that every 3 dB of gain added doubles the effective power output of an antenna. The more an antenna concentrates a signal, the higher the gain it will have. You can actually calculate the gains and losses of a system by adding up the gains and losses of its parts in decibels.

Frequency and Wavelength. Electromagnetic waves are comprised of two components: frequency and wavelength.

Frequency is how many waves occur each second. Wavelength is the distance between one peak of a wave and the next peak. Lower frequencies have longer wavelengths; higher frequencies have shorter wavelengths. For example, the frequency of AM radio is 1 MHz with a wavelength of about 1000 feet. FM radios operate at a much higher frequency of 100 MHz and have a wavelength of about 100 feet.

The two most common frequencies for wireless networking are 2.4-GHz and 5-GHz. Both are very high frequencies with very short wavelengths in the microwave band. The 2.4-GHz frequency has a wavelength of about 5 inches.

Beamwidth. Consider an antenna to be like a flashlight or spotlight. It reflects and directs the light (or radio waves) in a particular direction. Beamwidth actually measures how energy is focused or concentrated.

Polarization. This is the direction in which the antenna radiates wavelengths, either vertically, horizontally, or circularly. Vertical antennas have vertical polarization and are the most common. For optimum performance, it is important that the sending and receiving antennas have the same polarization.

VSWR and Return Loss. Voltage Standing Wave Ratio (VSWR) measures how well the antenna is matched to the network at the operating frequency being used. It indicates how much of the received signal won’t reach either the transceiver or receiver. Return loss measures how well matched an antenna is to the network. Typical VSWR numbers are 1:1.2 or 1:1.5. A typical return loss number is 20.

Microsoft Corp. has released another test version of an update to its virtualization software, which will be built into the next version of the Windows Server operating system.On Thursday, Microsoft released Beta 2 of Virtual Server 2005 Release 2 Service Pack 1 (R2 SP1), an update that will add new functionality to the existing version of Virtual Server 2005 once it is generally available. The software, which should be in full release by the first calendar quarter of 2007, can be downloaded for free.

New features included in Beta 2 of the software are support for Advanced Micro Devices Inc.’s virtualization technology, as well as new integration with Microsoft Active Directory, Microsoft said.

Beta 2 of Virtual Server R2 SP1 also includes new off-line virtual hard disk mounting, which enables customers to view and manipulate files in a VHD without having to start a virtual machine. This enables administrators to easily deploy scripts and perform virus scans across VHDs without having to start each virtual machine, Microsoft said.

The software also includes what is called a Volume Shadow Service, which improves the server backup process, according to Microsoft. Instead of scheduling downtime to back up each virtual machine individually, the software will take snapshots of physical machines. Those physical machines will in turn take snapshots of all the virtual machines on the physical host. This enables server administrators to keep virtual machines up and running even while backing them up.

The company introduced Virtual Server in October 2004. The product enables virtualization of Windows so multiple instances can run simultaneously on one server as if they were running on multiple servers.

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