\\_/ Now let us consider a mobile user M which is connected to the first base station 81 and is now at the boundary between the cells, as depicted in the figure above, with equal distance d = 1.5 km from both base stations. Other system parameters are: 0 Each base station and the mobile user are equipped with a single unit gain omni-directional antenna (i.e. antenna gain is one in the linear scale). a The transmit power at both base stations is Pr = 2 Watts. 0 The operating carrier frequency for both base stations is fc = 2 GHz. - The reference distance is do = 150 meters for both base stations. - The path loss exponent (beyond the reference distance) inside the first cell is :11 = 3.5. . The path loss exponent (beyond the reference distance) inside the second cell is :12, the value of which will be determined later. 0 Apart from path loss, the signal propagation from 31 to M is also affected by log-normal shadowing with standard deviation 0 = 8 dB. 0 There is no shadowing between 52 and M. Please answer the following questions: a) Find the received power in dBW of the desired signal transmitted from 31 to the mobile user M at d = 1.5 km, as a function of the shadowing random variable de. Note that de is a Gaussian random variable with zero-mean and standard deviation of a = 8 dB. (5 marks) b) Find the received power in dBW of the interference signal from 82 to the mobile user M at d = 1.5 km, as a function of g. (5 marks) c) Find the range of n2 that results in an average signal-to-interference ratio (SIR) of 7.5 dB or more at the mobile user M at d = 1.5 km. (3 marks) d) Assume :72 = 4.5. Find the probability that, due to shadowing, the actual SIR at the mobile user M at d = 1.5 km is below 7.5 dB. (4 marks) Note: You may use the Q-Function table provided in Wattle and round off numbers to the nearest value in the table. Let us cosider the cellular system, depicted in the figure below, where there are only two hexagonal cells with two base stations B1 and 82 located at the centre of cells. Both base stations are operated in the same frequency band. Mobile User Now let us consider a mobile user M which is connected to the first base station 31 and is now at the boundary between the cells, as