In this survey, we present a comprehensive list of the potential FD techniques and highlight their pros and cons. The main challenge encountered in implementing an FD wireless device is the large power difference between the self-interference (SI) imposed by the device's own transmissions and the signal of interest received from a remote source. Hence, the wireless research community aspires to conceive full-duplex (FD) operation for supporting concurrent transmission and reception in a single time/frequency channel, which would improve the attainable spectral efficiency by a factor of two. The family of conventional half-duplex (HD) wireless systems relied on transmitting and receiving in different time slots or frequency subbands. The results could be of immense assistance to radio frequency engineers for optimal statistical modelling and design of cellular systems channels. To accomplish the aim, eight probability distributions namely logistic, log-logistic, normal, log-normal, exponential, Rayleigh, rician and Gumbel max were explored and based on the combined scores of three goodness of fit statistical tests, the log-logistic distribution was found to be the optimal probability distribution for the weekly rate of drop call prognostic analysis. This work was designed to determine the optimal probability distribution model for drop call rates based on a five week acquired rate of drop calls data sample in the Southern regions of Nigeria.
Robust statistical estimation, modelling and characterization of call drop rates is of high importance to the network operators and radio frequency engineers for effective re-planning and performance management process of telecommunication system networks. The initiation and completion of an active call without any form of disconnection or termination is a key service quality parameter in telecommunication system networks. Any time a caller initiates and loses a connection to a BS while on conversation, the call is said to be dropped. When an active call is initiated by someone using a mobile phone, it is transmitted through a nearby Base Station (BS) transmitter to another BS until the call gets to its intended receiver. Mobile phones and handsets enable us to communicate our voice, data and video messages with individuals that are far-off from us.
It is hoped that this will serve as a one-stop shop for researchers and developers in the important field of wireless signal boosters and extenders, who wish to know what is available and existing challenges. In this paper, a survey of various signal booster designs, deployment and performance is presented. These boosters are diverse in make, range, method of operation, deployment and cost. Boosters are now giving hope to the frustrated wireless users such as indoor users and those at the fringes of a cell site. This problem has resulted in the development of cellular signal boosters that help in receiving the weak signal, amplifying and then re-transmitting it to reach the uncovered areas. As a result, the range of coverage may not be as planned leading to very weak reception or even dead zones where no communication can be done. One of them is that the radio frequency (RF) carrier signals used in these communication systems degrades as it travels through the air interface due to attenuation and interference. However, wireless communications faces a few challenges. Considering the hype of R&D in broadband technologies and easy acceptance in the market place, wireline communications may soon die a natural death. Both the wired and unwired environments are clamoring for wireless connectivity. Initially, the dawn of wireless was seen as the dawn of communications to poor countries and rural areas which were poorly covered by wireline devices due to high cost. Wireless is now dominating the telecommunications market. The beauty of wireless communication is that all nooks and corners can be reached at a cheaper and faster rate when compared with wireline.
The development of wireless technology has facilitated the wide deployment of mobile communication systems.
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