When we had landline phones, our calls wouldn’t drop if we could get through, but sometimes it would go to the wrong number. Despite being a wired connection, the landline calls went to many undesired receivers, creating quite a lot of stress and embarrassment.
It would take hours to fetch a trunk call (a long distance telephone call made within the same country). With wireless cellular phones, we don’t have to wait for hours to make a call, but quite often, the call drops.
The users have been complaining about it for a long long time and recently, a government minister had raised the issue of dropped calls during his parliament plenary.
Having said this, we all acknowledge that missing a call on our cellular phones is indeed a public concern and the people may want to know about why the calls actually drop.
First, let’s have a look at how a call flows. When a caller types a number on his or her cellphone, the call has to travel through at least 40 nodes before it reaches the receiver. This is how the technology works.
When a call goes out of a BTS (base trasceiver station), it has to go through ICX, IGW, IIG, and some fibre operators. A wireless call is very much susceptible to getting dropped when it has to cross 40 stages.
The authorities have a regulation in place that a mobile phone operator has to distribute its calls among all the licensed IIGs, ICXs, IGWs, etc. However, sometimes, those gateways fail to pay their dues and the authorities abruptly shut them down.
Now, what would the operator do? Recently, the authorities shut down four such gateways and the operators had to divert their traffic to others. And, perhaps, a million calls were dropped.
But everyone blamed the operator.
Problems in an operator’s internal gateways such as Base Station Controller, Mobile Switching Centre, etc can also cause call drops.
The shortage of spectrum is also an issue when it comes to call drops. The operators cannot afford to buy more spectrum as their return on investment won’t match with the exceptionally high fees that the authorities charge.
It’s worthwhile to mention that at this moment, about 185 megahertz of spectrum is lying unused. The authorities couldn’t sell them. The operators have been requesting the authorities to revisit the price of spectrum, which is currently one of the highest in the world.
The density of population could be another reason for a call to drop, no matter how strong the radio signal is. One BTS has a certain capacity for handling a certain number of calls. When a BTS gets overburdened due to too many calls, many don’t go through.
Take a cricket match in a stadium, for example. If we say that there are about four to five BTSs nearby and with the presence of 35,000 users in one single spot, they are bound to fail, aren’t they?
And if we take Dhaka’s Banasree, for example, it’s a Herculean task to reach every person in that area. The owners of the buildings aren’t agreeing to provide spaces to the operators to set up new towers.
There are hundreds of areas like Banasree. And despite that problem, everyone blames the operators.
Then, the sudden erection of a building can also cause a problem. The radio wave that you used to receive all this time is suddenly intercepted by a new building, creating havoc to your phone calls and data signals.
There are, of course, coverage gaps. Every inch of the landmass cannot be covered due to the sheer lack of the operators’ ability of construct towers across the country. There are several obstacles. The operators, even with the help of the tower companies, don’t get enough space to erect a tower.
Take Dhaka’s Shahbagh, DOHS, Baily Road, Cantonment, and border areas as examples. The operators are prohibited to place a BTS there in order to reach the people. Take a few areas where security is a priority and jammers are used. These jammers would, of course, lead to a call drop or a call getting muted.
The towers containing BTSs require steady flow of electricity. Come rain, come wind -- the power flow is stopped or rationed across the country. And when the power does not reach, the calls are bound to drop.
The cosmos of fibre is controlled by the NTTNs where operators have no control. They have to depend on the licensed fibre operators whose responsibility it is to lay and maintain the fibre.
When the fibre is cut due to construction work, the call is bound to drop. Moreover, the fibre licensees control the speed; and no matter how much speed an operator seeks, it gets exactly what the fibre company offers. The operators don’t have any other choice but to stick to the same fibre company.
It must also be mentioned here that call drops are a quality-of-service issue. The mobile phone operators have their guidelines for QoS, but other players in the ecosystem don’t.
We should also keep this aspect in mind while we work to reduce the number of call drops; we should also think of setting up guidelines of QoS for other operators.
Our handsets could also be another reason for call drops. The strength of receiving calls isn’t the same for all types of handsets. Malfunctions in the handsets themselves might also lead to call drops.
There are many reasons call drops might occur and it won’t be fair if we keep blaming the mobile operators for this. The industry average for call drops is about 0.8%, which is lower than the average of the developed world and within the ceiling of the telecom regulator.
Ekram Kabir is a story-teller. He can be reached at [email protected].
