m.jeya asked:




HTC Touch Diamond is having a 3.15 MP. It has 4 GB user available memory,192 MB DDR SDRAM, 256 MB ROM, Qualcomm MSM7201A 528 Mhz processor. Dimensions are 102 x 51 x 11.5 mm and Weight is 110 g. It supports GPRS, EDGE, 3G, Wi-Fi, Bluetooth v2.0 with A2DP and miniUSB.

HTC Diamond was released in May 2008, and was originally produced only in black.

The HTC Touch Diamond has a cool 3D interface and a beautiful touch screen. The Windows Mobile 6.1 smartphone also offers Wi-Fi, Bluetooth, GPS, and a 3.2-megapixel camera.

The smartphone is that much more stunning in person with its sleek mirrored face and the prism effect on the back. It’s also smaller than we originally thought at just 4 inches tall by 2 inches wide by 0.4 inch deep and 3.8 ounces, so you certainly won’t have any problems slipping this compact handset into a pants pocket.

The smartphone is outfitted with a gorgeous 2.8-inch, 680×480 pixel resolution touch screen. While this is all well and good, we think it may be the new TouchFLO 3D interface that really catches your eye. It builds on the TouchFLO interface that was first introduced on the HTC Touch, but the look and feel is completely different.

As for text entry, you can use the onscreen keyboard, which you can switch from full QWERTY to compact QWERTY to phone keyboard or other format, depending on your preference. On the other hand, when you have the keyboard open, it takes up about half of the screen, so if you’re entering text into any field on the bottom half of the screen, it’s covered up. Please Purchase Online http://www.phoneandbeyond.com/

LA Serve asked:


In the last 5 years there has been a significant increase in the popularity of wireless (Wi-Fi) networks. People can now access the Internet in the most unlikely of places: in bars, on the street or even in public parks. This increase in Wi-Fi usage has also been seen in many businesses, where employees regularly access the Internet away from their desks. But whilst the rise in popularity of wireless networks has brought with it many advantages, they continue to pose a number of significant security risks.

Additionally, with the widespread use of mobile phones, the airwaves are becoming increasingly congested. More powerful frequencies are being used and problems caused by E.M.I (Electro-Magnetic Interference) are becoming all the more prevalent.

Due to negligence and naivety, many users of Wi-Fi fail to adequately encrypt their networks. As a consequence, security breaches are very common as hackers can easily identify an insecure target and then exploit its weakness. And although some security breaches may be relatively minor (i.e. an outsider using the wireless Internet connection to browse the Web), some breaches may be severe, leading to credit card fraud or even corporate espionage!

The popularity of ‘War Driving’ – a term for locating vulnerable wireless hotspots whilst driving a vehicle and using laptops – only exacerbates the situation. But the problem is not limited to wireless Internet access. As more people turn to mobile communication devices, we see an increasing number of Bluetooth intrusions, particularly by hackers and scammers, wishing to prey on insecure mobile phones. The fact is: if a device omits a signal to carry data to another location, those with sufficient knowledge can potentially target it.

Although Wi-Fi signals have the ability to transmit through walls, the greatest amount of leakage occurs through windows. In buildings with a significant amount of glass, this leakage can be quite considerable, with modern developments often containing a great deal of glass – over 70% in some cases. This obviously increases the likelihood of a wireless security breach, but ultimately the level of shielding is dependent on the building structure itself.

However, a development in the form of reflective Window Film can reduce leakage and help avert eavesdropping from potential hackers. It can also reduce the “signal signature”, helping networks to hide more effectively from scanners. If it is more difficult for a hacker to locate your wireless network, it will be much harder for him or her to compromise your security.

Whilst it is difficult to completely contain a wireless signal, the application of Window Film can assist in reducing the external threat. A less conspicuous signal equates to a lower security risk. And since transparent window film also allows light to pass through naturally, passers by will be non the wiser. This can have tremendous benefits especially if the user handles sensitive information or operates a number of different signal devices.

Anti-Spy Window Film comprises aluminium and titanium sputter coated polyester in several layers, including a scratch resistant protective coating. When tested in accordance with ASTM D 4935, the “Standard Test Method for Measuring the Electromagnetic Shielding Effectiveness of Planar Materials”, these films attain a 90-99% effectiveness score. It is important to remember that performance levels are severely affected by ‘edge gaps’ and so the best figures are achieved by combining the film installation with a metal secondary frame to cover these areas. This will ensure that signal leakage is kept to an absolute minimum.

In summary, if your business premises contain a large amount of glass (and if you regularly use wireless devices), it may prove worthwhile to invest in Window Film. With a wide range of Window Films available, including those for safety, security, privacy and solar control, a solution can be found to even the most challenging of problems.

Darlene Kaitlene asked:


In a shrinking world (thanks to technological advancements), it is suicidal to stay ensconced into one’s own world and not venture out to lands of immense possibilities. The mantra for today is think global! But how can you think global if you can not communicate freely with the world outside? It is difficult.

Well, technological advancement is the cause and consequence of the need for smooth communication. And that is the reason – today we have VoIP solution like NETGEAR SPH101VOIP Skype Wi-Fi Phones. NETGEAR SPH101VOIP Skype Wi-Fi Phone is a wireless mobile phone which enables you to make free internet calls to those who have Skype or Wi-Fi wireless Internet connection.

You can make calls with NETGEAR’s SPH101VOIP Skype Wi-Fi Phone without the requirement of a desktop or laptop. All you need is a Wi-Fi network around you so that you are online. Just like you do with a PC, you can also make free calls to Skype users around the world at any time.

The NETGEAR’s SPH101VOIP Skype Wi-Fi Phone has colour display quite similar to your laptop. The screen will show all your friends who are online. This way you are always connected to your friends, colleagues and clients whether or not you are near your PC.

Apart from calls to other Skype numbers, you can also make calls to any phone in any part of the world for just a few pennies per minute. And what more, you do not have to pay any other monthly fees apart from the Skype Call charges. Besides this, you can forward your calls to your mobile, land-line or to another Skype ID.

NETGEAR SPH101VOIP Skype Wi-Fi Phones are ideal both for your work and for your fun times. You can do all that you can do with your Skype id on this phone. This is a cool VoIP solution, which is available with leading online web stores.

Tamoor Akbar asked:


Wi-Fi Technology

  Written By

Tamoor Akbar

(National Textile University,Pakistan)

October2008

                                                                   

  

 

 

 

 

What is WiFi ?

Wi-Fi is new technology enabling images from a computer to be transmitted to the projector without a hard-wire connection. Hence the use of a VGA cable to connect the computer and the projector is no longer required.

 

Why Wi-Fi?

The purpose of Wi-Fi is to hide complexity by enabling wireless access to applications and data, media and streams. The main aims of Wi-Fi are the following:

make access to information easier ensure compatibility and co-existence of devices eliminate cabling and wiring eliminate switches, adapters, plugs, pins and connectors.

 

 

How wi-Fi works?

 

It uses a new technology, which for the purpose of transmission of information over greater distances. Put simply, WiFi can transmit information up to ten times faster than Bluetooth, and up to six times further than Bluetooth.WiFi networks use radio technologies called IEEE 802.11b or 802.11a to transmit data from the internet connection to the host computer (e.g. your laptop). These technologies provide reliable and fast wireless connectivity and to some degree a level of security (to be addressed below). A Wi-Fi network can be used to connect computers to each other, to the Internet, and to wired networks.

 

 

Wi-Fi networks operate in the unlicensed 2.4 and 5 GHz radio bands, with an 11 Mbps (802.11b) or 54 Mbps (802.11a) data rate or with products that contain both bands (dual band), so they can provide real-world performance similar to the basic 10BaseT wired Ethernet networks used in many offices

Elements of a WI-FI Network

 

 

 

•         Access Point (AP) - The AP is a wireless LAN transceiver or “base station” that can connect one or many wireless devices simultaneously to the Internet.

 

•         Wi-Fi cards - They accept the wireless signal and relay information.They can be internal and external.(e.g PCMCIA Card for Laptop and PCI Card for Desktop PC)

 

•         Safeguards - Firewalls and anti-virus software protect networks from uninvited users and keep information secure.

 Limitations

 

 •         Interference

•         Degradation in performance

•         High power consumption

•         Limited range

 

 

 



Uses

 

 

·        Wi-Fi enabled device such as a PC, game console, mobile phone, MP3 player or PDA can connect to the Internet when within range of a wireless network connected to the Internet. The coverage of one or more interconnected access points — called a hotspot — can comprise an area as small as a single room with wireless-opaque walls or as large as many square miles covered by overlapping access points. Wi-Fi technology has served to set up mesh networks,

 

·        In addition to restricted use in homes and offices, Wi-Fi can make access publicly available at Wi-Fi hotspots provided either free of charge or to subscribers to various providers. Organizations and businesses such as airports, hotels and restaurants often provide free hotspots to attract or assist clients. Enthusiasts or authorities who wish to provide services or even to promote business in a given area sometimes provide free Wi-Fi access. Metropolitan-wide Wi-Fi (Muni-Fi) already has more than 300 projects in process.[2] There were 879 Wi-Fi based Wireless Internet service providers in the Czech Republic as of May 2008.

 

·        Wi-Fi also allows connectivity in peer-to-peer (wireless ad-hoc network) mode, which enables devices to connect directly with each other. This connectivity mode can prove useful in consumer electronics and gaming applications.

 

·        Many consumer devices use Wi-Fi. Amongst others, personal computers can network to each other and connect to the Internet, mobile computers can connect to the Internet from any Wi-Fi hotspot, and digital cameras can transfer images wirelessly.

 

·        One can also connect Wi-Fi devices in ad-hoc mode for client-to-client connections without a router.

 

In wake of recent mining tragedies, some technology companies have suggested extension of wireless real-time location technology using WiFi networks to pinpoint miners trapped underground – a solution that could save lives in the future.

 

           

 Wi-Fi technology has spread widely within business and industrial sites. In business environments, just like other environments, increasing the number of Wi-Fi access-points provides redundancy, support for fast roaming and increased overall network-capacity by using more channels or by defining smaller cells. Wi-Fi enables wireless voice-applications (VoWLAN or WVOIP). Over the years, Wi-Fi implementations have moved toward “thin” access-points, with more of the network intelligence housed in a centralized network appliance, relegating individual access-points to the role of mere “dumb” radios. Outdoor applications may utilize true mesh topologies. As of 2007 Wi-Fi installations can provide a secure computer networking gateway, firewall, DHCP server, intrusion detection system, and other functions.

Growth of Wi-Fi technology in some previous years clearly shows Wi-Fi will cannibalize all other wireless technologies.We can say “the future is of Wi-Fi”.

 

 

 

Paul Ngai asked:


Some 70 – 80% of mobile traffic originates from inside buildings. This is especially true in urban environments where the focus of the mobile user is on high data rates. For mobile 3G network, only serving macro base station within a few hundred meters of the building can provide sufficient level of RF signal to support indoor voice/data services. In realty, only a few buildings will fall into this category. Soft handover in 3G network will further increase the traffic load on the network since each indoor mobile phone can be serviced by more than one macro cells (base stations). In order to provide indoor high speed mobile data services such as HSPA (High speed Packet Access) or EVDO (Evolution – Data Optimized) services, the only solution is an indoor Distributed Antenna Systems (DAS).

DAS is used to distribute the RF signal evenly with sufficient strength inside a building to provide 3G voice and data services. DAS can be used to isolate the indoor network from the outdoor serving macro cells to eliminate the soft handover of the indoor mobile phone. This will reduce the traffic load and increase the speed of the 3G network. For HSPA high speed data service, indoor DAS can also provide isolation between serving and non-serving cells of the outdoor network. This means less co-channel interference in the HSPA serving cell and results in higher data rate for the HSPA service. To dominate the building with indoor coverage, directional antennas can be deployed at the edge and corners of the building and pointing towards the center of the building. The total indoor area is dominated by the indoor cell and at the same time minimizes leakage to the macro network.

DAS distributes a uniform dominant RF signal inside the building by splitting the signal from the indoor base station to multiple indoor antennas to provide coverage throughout the building. DAS can be classified as passive or active. Passive DAS uses passive components to distribute the RF signal. These passive components are coax cable, splitters, terminators, attenuators, circulators, couplers and filters (duplexer, diplexer or triplexer). Planning DAS includes calculating the maximum loss from base station to each antenna in the systems and does the link budget for the particular area that each antenna covers. The passive DAS design needs to adapt to the limitation of the building regarding the restriction to where and how the heavy coax cable can be installed. A detail site survey of the building needed to be done to make sure that there are cable routes to all antennas.

Active DAS has the ability to automatically compensate for the losses of the cables interconnecting the components in the system by using internal calibrating signals and amplifiers. It does not matter what the distance between the antenna and the base station, all antennas in an active DAS will have the same performance (same noise figure and downlink power). Active DAS consists of a master unit (MU) connected to multiple expansion units (EU) with optical fiber up to 6 km in length. Each EU in turns connects to multiple remote units (RU) with thin coax or CAT5 cable up to 400m in length. The MU controls and monitors the performance of the DAS. The EUs are distributed throughout the building and the RUs are installed close to the antenna. A wideband active DAS can support multiple radio services, GSM, PCS, UMTS, EVDO, WiMax and WiFi.

Due to the loss and attenuation in the coax cable and passive components, passive DAS is only used in smaller building covers by a small number of indoor antennas to keep its degrading impact on HSPA performance to a minimum. For larger building, active DAS is used because it does not have cable and component loss and can boost the HSPA performance to the maximum. Troubleshoot in passive DAS is difficult and any fault in the systems will not raise an alarm at the base station because there is no surveillance of errors in the system. Active DAS monitors all units in the system and in the event of malfunction; it will send an alarm to the base station which enables the operator to pinpoint the source of the problem. Hence, active DAS is the preferred solution for large building with a lot of indoor antennas.

George Scifo asked:


The key value of any wireless product is its ability to deliver the necessary capacity over an area of coverage at a cost that enables a favorable return on investment.

The impediment to achieving this simple goal is RF signal attenuation, which imposes constraints when balancing the contradictory objectives of close proximity (to enhance capacity) and long range (to extend coverage and lower costs). For example, a point-to-multipoint base station at a tower provides high capacity to subscribers in close proximity but capacity lessens over distance. To resolve capacity degradation, a point-to-point link can be deployed from the tower to a remote point-to-multipoint base station optimally situated to provide better proximity and increase capacity but at a significant increase in costs.

The best way to summarize the mutual exclusivity of close proximity and long range is the expression:

“Cost, Coverage, and Capacity: Pick Any Two”

Broadband wireless, therefore, is defined by these limitations:

1. Low cost and long range, but with low capacity.

2. Low cost and high capacity, but only at short range.

3. Long range and high capacity, but at a high cost

SkyPilot, however, has a patented broadband wireless system that helps overcome these limitations. Although still bound by RF signal attenuation, SkyPilot is able to provide breakthrough economics to wireless operators by extending coverage and improving capacity through an innovative wireless architecture called SyncMesh™.

SyncMesh – Redefining Broadband Wireless

To confront the seemingly impossible goals of high capacity, long range, and low cost, SkyPilot developed a patented Synchronous Switching broadband wireless system. These systems, when coordinated by the SyncMesh™ protocol, dynamically align high-gain directional antennas throughout an entire network of interconnected base stations.

With this architecture, every base station covers 360° through eight individual 45° antennas. The base station dynamically switches between these high-gain (18 dBi) antennas to provide both long-range point-to-multipoint links to CPE as well as long-range point-to-point links to other base stations. By dynamically interconnecting base stations with point-to-point link, SyncMesh can enable multi-hop wireless networking, with each base station functioning as a “relay” to extend the total coverage area. Therefore, with dynamic antenna switching, each system integrates a point-to-point backhaul, multi-hop relay, and point-to-multipoint base station within a single system to extend range and keep costs low.

Note, however, that SyncMesh does not simply repeat the signal, since that is an inefficient and wasteful use of spectral capacity. Instead, SyncMesh coordinates and synchronizes transmissions to maximize network-wide capacity. By allowing multiple simultaneous narrow-beam transmissions, SyncMesh mitigates self-interference and leverages spatial diversity to maximize spectrum reuse, resulting in efficient capacity utilization throughout the entire spectrum.

With the SyncMesh protocol coordinating the alignment of directional antennas, SkyPilot has been able to redefine broadband wireless as:

“Cost, Coverage, and Capacity: Pick Any Three”

Coverage Extension

To extend the coverage served by each cell tower, SyncMesh uses a combination of high-gain directional antennas and multi-hop relaying at every base station in the network. High-gain directional antennas are, of course, one of the best methods to increase range since it increases the link budget for both transmit and receive. They also enable many of the advanced SyncMesh features such as spectral reuse and self-interference mitigation.

Long Range Point-to-Point Backhaul Links

At synchronized time slots, each and every SyncMesh node dynamically switches to the optimal high-gain antenna for transmission coordination. Since each backhaul link has a directional 18 dBi antenna at each end, the SyncMesh nodes leverage 36 dBi of gain to provide a line-of-sight (LOS) link of up to 10 miles/16 km. These links can also support non-line-of-sight (NLOS) through OFDM modulation; however, the ranges of NLOS links vary, of course, depending on the type and amount of obstructions.

Multi-Hop Relay Range Extension

Through the multi-hop relaying capability, each base station can act as a relay node as well. This allows the range covered from a cell tower to extend over multiple hops, with each “hop” extending range by up to 10 miles/16 km as indicated earlier. With multi-hop relay capabilities, the reach from the tower is no longer limited to a single base station; instead, the reach from the tower can be greatly extended through a series of interconnected base stations.

Long Range Point-to-Multipoint Links

The same dynamically switched 18 dBi antennas are also used for point-to-multipoint links. With point-to-multipoint, the base station connects with SkyConnector customer premise equipment (CPE), which also has a high-gain directional antenna. With these high-gain antennas, high-power radios, and OFDM links, the base station can provide LOS links to CPE as far away as 7.5 miles/12 km.

Coverage Fill-in by Routing Around Obstructions

Extending coverage is not just about pushing out the boundary of a coverage cell – coverage extension also applies to filling in coverage holes. Since SyncMesh provide multi-hop relay capabilities, remote base stations can be routed around obstructions to easily reach and fill-in any holes in coverage.

Capacity Efficiencies

SyncMesh is specifically designed to make the most efficient use of available spectrum over an entire mesh of base stations. When the entire mesh of directional links is viewed as a whole, the SyncMesh protocol enables multiple links to transmit using the same frequency with limited self-interference through a distributed synchronous protocol. This enables optimal spectrum reuse throughout an entire coverage region to increase the total “goodput” per second of airtime.

OFDM with Adaptive Modulation

All SyncMesh links use OFDM to provide the best ability to close high-modulation rate links, even in NLOS environments. The links are constantly monitored and modulation rates periodically adapt to any changes in the wireless environment to ensure optimal performance.

Spatial Spectral Reuse

One of the main benefits of the mesh-wide coordinated transmission pattern is the idea of “spatial spectral reuse”. Since SyncMesh coordinates all of the dynamic directional links, multiple simultaneous transmissions occur on the same frequency, effectively reusing the spectrum throughout the entire coverage region.

High Modulation Rates

Since SyncMesh nodes all carry multi-hop point-to-point backhaul, they can easily be deployed in close proximity to subscribers. This allows the ability to convert “cell edge” low-modulation subscribers to high-modulation subscribers through better proximity. With this capability, the network-wide average modulation rate increases and optimizes the “goodput” by enabling more frequent higher-throughout transmissions throughout the network.

Self-Interference Mitigation

As a result of dynamically switching directional antennas and synchronizing the reuse of the spectrum, SyncMesh uses spatial diversity to effectively mitigate self-interference, resulting in further improving modulation rates and overall spectral efficiency.

Linear Capacity Scalability through Spectral Layering

Since SyncMesh maximizes the spectral efficiency of a single frequency by optimally reusing the channel over a wide coverage range, it enables the use of alternative channels to linearly scale capacity. “Layering” alternate channels throughout the coverage region makes maximum use of available frequencies.

Breakthrough Economics

Through the technical advantages of greater coverage range and more efficient spectrum utilization, a large amount of bandwidth can be propagated from a single capacity injection point. When combined the other SyncMesh features, this leads to significant economic advantages.

Multi-Hop Coverage Extension Reduces Towers Costs

Multi-hop backhaul greatly increases the coverage radius of a single tower, thereby reducing the number of towers required to provide broadband services over a given coverage area. Reducing the number of towers required directly lowers the associated tower acquisition and lease costs as well as the number of leased or microwave backhaul connections required for each site.

Integrated Backhaul, Relay, and Base Station Reduces Capital Costs

The unique integration of a point-to-point backhaul, a multi-hop relay, and a point-to-multipoint base station leads to a significant reduction in network capital costs. Since these distinct functions are not discrete products, there are no additional costs because they are simply integrated into a single networking system. The ability to reuse the radio for different functions by dynamically switching directional antennas lowers the overall costs of deploying broadband wireless.

In addition, there is only a single point-of-attachment. He said we should mention that 360 coverage for Gateways and Extenders means you only need to pay for one attachment to a tower. Most of the company’s that rent tower space charge for each attachment.

Automatic Discovery and Automatic Antenna Pointing Reduces Operating Costs

The ability of SyncMesh to automatically discover all nodes and dynamically and automatically point directional antennas leads to a dramatically decrease in operating expenses. Since each SyncMesh product can covers 360° by dynamically switching to any of eight separate 45° directional antennas, there is no manual antenna pointing required, regardless of whether the links are point-to-point, relay, or point-to-multipoint. SyncMesh automatically discovers all nodes and automatically configures each and every link, which reduces the operational cost associated with deploying an advanced broadband wireless network. This minimizes the “hands-on” operational expertise and reduces the overall time to deploy.

Additional Benefits Derived from SyncMesh

In addition to all of the aforementioned benefits, the SyncMesh architecture also provides additional features that provide benefits to wireless operators.

Best-Path Routing, Dynamic Rerouting, and Self-Healing Failover

SyncMesh has the ability to determine if multiple routes are available and to choose the optimal path. In addition, if modulation rates change or the network configuration changes, the mesh of interconnected point-to-point backhaul links can automatically and dynamically adapt. This optimizes throughput and can provide self-healing capabilities in case of failures.

Latency Guarantees

Since SyncMesh is a synchronized protocol, it can provide low latency, low jitter, and guarantees for latency-sensitive traffic such as VoIP.

Wireless Backhaul for Wi-Fi Access

With the synchronous wireless mesh network operating in the 5 GHz frequency band, it allows each mesh node to also provide Wi-Fi access services. All SkyPilot mesh nodes are available with Wi-Fi access points (APs) at 2.4 and 4.9 GHz. This allows Wi-Fi access to be spread over large coverage areas.

“Ethernet In/Ethernet Out”

Each SyncMesh network is a full Layer 2 network, which results in “Ethernet In/Ethernet Out” across the network. This Layer 2 architecture supports virtual LANs (VLANs) and a full range of Layer 3 protocols including IPv4 and IPv6. In addition, when used as the backhaul for Wi-Fi access, mobile devices are not required to renew their IP address since they are not crossing subnet boundaries. 21BFrequency Flexibility Each high-gain directional antenna support a range of frequencies from 4.940-6.075 GHz. This allows each node to provide frequency flexibility and give operators the ability to change to new frequencies as required.

Summary

Although all wireless products are bound by the laws of physics, innovations solutions can help alleviate some of the fundamental constraints. The SyncMesh protocol leverages the notion of high-gain directional antennas to increase range and capacity, but through its patented method of switching between antennas, still provides the cost advantage associated with omnidirectional antenna systems. In the end, SkyPilot has been able to redefine broadband wireless to “Cost, Coverage, and Capacity: Pick Any Three”