Um estudo sobre as principais causas de quedas de chamadas em célula de rede móvel GSM é realizado por meio da análise estatística do tráfego. O objetivo é minimizar o efeito dessas causas, por meio da alteração de parâmetros de cobertura, como controle dinâmico de potência, borda de cobertura entre células e definição correta de células vizinhas. Para uma operadora celular reduzir a taxa de queda de chamadas (TQC), por intermédio da otimização de parâmetros de cobertura, alterados via comandos remotos, elimina os custos com alterações físicas, como altura das antenas e instalações de novas estações rádio base. Entretanto, alterações de parâmetros devem ser cuidadosamente realizadas, pois podem degradar outros indicadores e acarretar redução da área de cobertura e do tráfego. As duas principais causas da TQC são as quedas repentinas, ocasionadas por falha nos equipamentos envolvidos, ou comportamento dos assinantes e falha na execução do handover e as quedas devido ao nível baixo de sinal na interface aérea. Neste trabalho, com base em dados estatísticos do tráfego na rede GSM, foi escolhida uma célula operando em 900 MHz que apresentava alta TQC. Ajustando os parâmetros de cobertura, a TQC mensal passou de 8,6% para 1,6% e não houve degradação nos demais indicadores de desempenho. / A study about the main causes of dropped calls in mobile network cell GSM is made by means of statistical traffic analysis. The aim is to minimize the effect of these causes through coverage parameters changes, such as dynamical potency control, coverage border between cells, correct definition of neighboring cells. The reduction of dropped call rate by means of optimization of coverage parameters, changed via remote commands, eliminates costs with physical changes, such as the height of the antennas and installation of new radio base station. Parameter changes, however, must be carefully made because they can degrade other indicators and bring coverage area and traffic reduction. The two main causes of dropped call are sudden loss of connection, due to failure in the equipment used, behavior of subscribers and the failure in handover and drops due to the low signal strength in the air interface. In this study, based on statistical data of GSM traffic, a cell operating in 900 MHz that presented high dropped call rate was chosen. Adjusting the coverage parameters, the monthly dropped call rate went from 8.6% to 1.6% and there wasn\'t any degradation of any other performance indicators.

<p>Nowadays, GPS Mobile has already become important part of our life. GPS is widely used for citizen and military. For military, they could use GPS to navigate the missile or space flight. For citizen, people use GPS, especially GPS Mobile, to navigate car. GPS also helps people to find their way to home. GPS are widely use on, police, company manage system, agriculture and so on. GPS Mobile is the most familiar device for all of us to use. To combine use GPS Mobile and Google Map, people can get their currently location and shortcut to their destination. Also, we can get information from the Google map, like shopping place, bus station and so on. The main purpose of our project is to help people reach this aim. By using our software, you can find your location on the Google map. When you travel abroad, you can have your own language map on the GPS mobile, easily and quickly. That’s really convenience. The most wonderful part, you can play game with your friend by using our software. What you need to do, it is just send a message to anyone you care about and then you can get their location and show it on the map. So, even it is a far distance between you and your friend. You can have fun together. That is our software Findyourfriendlocation.</p>

Um estudo sobre as principais causas de quedas de chamadas em célula de rede móvel GSM é realizado por meio da análise estatística do tráfego. O objetivo é minimizar o efeito dessas causas, por meio da alteração de parâmetros de cobertura, como controle dinâmico de potência, borda de cobertura entre células e definição correta de células vizinhas. Para uma operadora celular reduzir a taxa de queda de chamadas (TQC), por intermédio da otimização de parâmetros de cobertura, alterados via comandos remotos, elimina os custos com alterações físicas, como altura das antenas e instalações de novas estações rádio base. Entretanto, alterações de parâmetros devem ser cuidadosamente realizadas, pois podem degradar outros indicadores e acarretar redução da área de cobertura e do tráfego. As duas principais causas da TQC são as quedas repentinas, ocasionadas por falha nos equipamentos envolvidos, ou comportamento dos assinantes e falha na execução do handover e as quedas devido ao nível baixo de sinal na interface aérea. Neste trabalho, com base em dados estatísticos do tráfego na rede GSM, foi escolhida uma célula operando em 900 MHz que apresentava alta TQC. Ajustando os parâmetros de cobertura, a TQC mensal passou de 8,6% para 1,6% e não houve degradação nos demais indicadores de desempenho. / A study about the main causes of dropped calls in mobile network cell GSM is made by means of statistical traffic analysis. The aim is to minimize the effect of these causes through coverage parameters changes, such as dynamical potency control, coverage border between cells, correct definition of neighboring cells. The reduction of dropped call rate by means of optimization of coverage parameters, changed via remote commands, eliminates costs with physical changes, such as the height of the antennas and installation of new radio base station. Parameter changes, however, must be carefully made because they can degrade other indicators and bring coverage area and traffic reduction. The two main causes of dropped call are sudden loss of connection, due to failure in the equipment used, behavior of subscribers and the failure in handover and drops due to the low signal strength in the air interface. In this study, based on statistical data of GSM traffic, a cell operating in 900 MHz that presented high dropped call rate was chosen. Adjusting the coverage parameters, the monthly dropped call rate went from 8.6% to 1.6% and there wasn\'t any degradation of any other performance indicators.

Nowadays, GPS Mobile has already become important part of our life. GPS is widely used for citizen and military. For military, they could use GPS to navigate the missile or space flight. For citizen, people use GPS, especially GPS Mobile, to navigate car. GPS also helps people to find their way to home. GPS are widely use on, police, company manage system, agriculture and so on. GPS Mobile is the most familiar device for all of us to use. To combine use GPS Mobile and Google Map, people can get their currently location and shortcut to their destination. Also, we can get information from the Google map, like shopping place, bus station and so on. The main purpose of our project is to help people reach this aim. By using our software, you can find your location on the Google map. When you travel abroad, you can have your own language map on the GPS mobile, easily and quickly. That’s really convenience. The most wonderful part, you can play game with your friend by using our software. What you need to do, it is just send a message to anyone you care about and then you can get their location and show it on the map. So, even it is a far distance between you and your friend. You can have fun together. That is our software Findyourfriendlocation.