Craftily Designed Mobile Article?
I turned off my TV then programmed the VCR to tape ER. I left ASAP and SMS’ed my GF on the way to the CBD to RSVP for the VIP dinner at the YMCA. It was then that I passed the DIY shop, STA travel agent, UTS and stumbled across the BYO mobile phone shop. My last phone was now officially DOA and as for a new phone, that was TBC. Then I stopped. Straining my eyes to look at the sign, I read out the letters in front of me…CDMA?
Confusing, Demented Mobile Acronym?
Surprisingly, I was not alone in my ignorance of CDMA. Even a store person at a local telecommunications retailer (who shall remain nameless for the sake of keeping their pride and dignity) didn’t have a clue. The fact is that many Australians are completely unaware of what CDMA is, what it does, what it’s good for and what it stands for. Well, not for long…
Craftily Disguised Mobile Acronym?
CDMA stands for Code Division Multiple Access - and like most names, this means nothing unless one knows what its purpose is. Let’s start from the very beginning. A long time ago in a galaxy not very far away at all, there were two different kind of mobile phone network; analogue (or analog) and digital. The two networks worked in very different ways and each had its own advantages (analogue for example tended to not drop out as much and digital could afford smaller handsets).
For the turn of the century, the Australian government and relevant communications bodies decided to phase out the analogue network in favour of the developing digital network. This resulted in the majority of phones becoming digital and working on the GSM digital network and most phones you encounter today will be on this GSM network.
However, the GSM network had a very limited range, needing lots of base stations in relatively close proximity to each other. This is fine for city living where they can be attached to buildings with not much hassle. But for rural living, there are vast distances to cover and installing many base stations to reach across these distances is just not practical. So, as a solution, the CDMA network was introduced. Instead of only using one band of radio frequencies as GSM does, CDMA divides the signal between two bands allowing less drop outs and a generally stronger signal.
Advantages of CDMA
The main advantage of a CDMA network is that the handset can be at least twice as far away from a base station before dropouts occur, when compared to a GSM network. This meant that for rural areas where they may be several tens of kilometres away from a town with a base station, some reception was possible. Most of the main highways through Australia are now covered by the CDMA network (depending on which provider you are with, read “CDMA options” for more details) - filling in the gaps where GSM could not reach.
Disadvantages of CDMA
The other great advantage of CDMA is built into the handset. This is a form of noise reduction exclusive to CDMA where background noise is suppressed so that the result is a clearer voice for the receiver. For example, if you were standing in a large crowd at a shopping centre talking on your mobile phone, with a GSM phone there would be significantly more of the crowd being heard at the other end of your conversation than there would be had you been using a CDMA handset.
Apart from these two points, CDMA does not differ greatly from GSM and performs almost all the same functions.
The main disadvantage that CDMA possesses is the lack of international roaming capabilities. International roaming is when the handset can be used in another country other than Australia and is possible when that country has a similar network to ours. With GSM phones it is as simple as having a phone which can operate on several different bands (dual or triple band) and switching to the appropriate band when in a different country. With CDMA, at present, there are
a few other compatible networks in other countries, but the cost involved to
provide the service to a relatively small number of roaming CDMA user is
completely unfeasible, so international roaming is impossible.
With CDMA, the ability to upgrade or change to another handset isn’t as easy as for GSM phones. The network service information for a CDMA phone is actually put into the actual phone and not like the ability of GSM models - where the SIM card holds this information instead. Most GSM users would have realised by now that if their phone was to become unusable (for example, a flat battery or become faulty), he or she can take their SIM card out and put it in another compatible phone where calls are made and received from the same phone number.
Another disadvantage is the limited variety in handsets available. Because GSM holds most of the mobile phone market, the major phone manufacturers tend to make and develop GSM phones in preference to CDMA.
Again, apart form these points, CDMA functions just the same as GSM, allowing all the same tasks to be performed.