With phones, PDAs, MP3 players and GPS devices embracing digital music, photos, videos and mapping content, ways to connect to PCs and other devices become vitally important. Here are your wireless connectivity options and the pros and cons of each one.
Infrared
Infrared Infrared (IR) ports on handhelds are useful for short-range, low-bandwidth data transfers, but you will need a clear line of sight for the two devices to communicate with each other, as with TV remote controls. If your laptop has an IR port, for example, you'll be able to synchronise without a cradle or a cable -- a particularly handy feature for road warriors. And if your handheld is equipped with the proper software, you can even use infrared to control your TV and other home entertainment devices. Note that this wireless option is becoming less popular these days and many newer models leave it out altogether.
Infrared ports allow short-range data transfer from
your handheld to another device, such as a laptop.
Bluetooth
This short-range radio frequency (RF) technology operates on a 2.4GHz spectrum and allows devices to communicate with other Bluetooth-enabled gadgets; thus, you can dial numbers straight from your PDA's contact list or use your mobile phone as a modem to check e-mail. You can also transfer files, print to a Bluetooth printer or sync with a Bluetooth-equipped computer. Unlike IR, Bluetooth's RF signals can travel through clothing and other barriers, meaning you can leave your phone in your pocket and still be connected to your PDA. Almost all modern handhelds come with Bluetooth built-in. This is especially important for PDA-phones as wireless headsets usually connect to them using Bluetooth. Additionally, if you wish to use a wireless Bluetooth stereo headset for music, the device must also support the A2DP profile. Bluetooth 2.0 is the latest revision of this wireless technology and is an improvement over the previous version in both speed and battery efficiency.
Wireless LAN networking
With a Wi-Fi-enabled handheld, you can connect directly to the Internet at high speeds to check e-mail, browse the Web, and even access servers via secure virtual private network (VPN) connections. Like Bluetooth, Wi-Fi runs on a 2.4GHz spectrum, and you need to be near (typically 45 to 90m from) an access point in order to connect. If your handheld doesn't come with built-in Wi-Fi, you can purchase Wi-Fi networking cards (usually in the form of SDIO cards) to get connected. Additionally, Wi-Fi requires a lot of power and quickly drains most PDA batteries.
No integrated Wi-Fi? No problem. With a Wi-Fi card
and expansion slot, you can connect to the Web in a flash.
The majority of handhelds use the 802.11b/g standards, which are the same ones found in most common public hot spots, such as cafes and airport lounges. Data can be transmitted at maximum speeds of 11Mbps for 802.11g and 54Mbps for 802.11g. These two standards are compatible with each other -- you can connect an 802.11g handheld to a 802.11b network, and vice versa. Take note that in such a mixed network, the maximum speed possible will be limited by the slower 802.11b standard. A large number of devices now sport this wireless option, and is increasingly being regarded as a standard feature for handhelds.
Wireless WAN networking
Wi-Fi works great when you're close to a hot spot but not if you wander far and wide. The declining popularity of the dedicated PDA is due largely to the integration of cellular radios into handhelds so that they double up as mobile phones. The rate at which this area of wireless networking has improved is astounding, with data speeds capable of hitting 3.6Mbps (theoretically) using HSDPA, an extension of 3G technology.
PDA-phones, such as the Samsung Blackjack,
stay connected via wireless WAN.
Without 3G coverage, PDA-phones are still capable of data transfer using GPRS. Though agonizingly slow, it is available wherever there is GSM coverage. Users do have to take note that downloading data using mobile networks usually incurs additional charges, which can amount to quite a hefty bill from your operator depending on the volume of data transferred. PDA-phones range from the basic triband GSM devices to those which support HSDPA like the O2 Atom Life.
Global Positioning System
More handhelds are now sporting GPS functions with the inclusion of built-in GPS chips. This is slightly different from the wireless features discussed above because instead of data transfers, these chips locate and connect to satellites which will then give the location of the device. This is commonly used together with maps to determine driving routes and can be very useful for those traveling in unfamiliar countries. Users must note that GPS receivers are extremely power-hungry and can deplete a handheld's battery very quickly. An extra battery or a car charger when going on an extended trip are essential accessories when using GPS navigation.
Peter
08/11/2007 01:51 AM
I would be happy seeing some useful links on how to configure these sdio-s.
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