Environmental authorities have proposed to the government a sensor system that can detect the level of pollution in different parts of the city in real time. The idea is to place at least 150 sensors scattered throughout the entity. These sensors will be connected through the \( 5 \mathrm{G} \) standard to information hubs (32 to be exact, 2 per territorial demarcation). These hubs will be in charge of processing the information in real time and generating automatic reports, which will be sent electronically to a server of the city's C5 through twisted pair.
In the case of the sensors, it is known that they will be loT devices operating in a band from \( 3.52 \) to \( 3.62 \mathrm{GHz} \), in addition to being braced elements with a maximum power of \( 80 \mathrm{~W} \) and a maximum voltage of 135 [V], with a latency lower than \( 3 \mathrm{~ms} \). For its operation, the following aspects will be considered:
- The devices must have at least 4 frequency channels, with a guard of at least \( 5 \mathrm{MHz} \) between each of the channels.
- For the processing of the signals that carry information, it is required that these be of very good quality to avoid errors, which is why a low-pass filter will be used. Although the voltage variation of the signals at the output of said signal is not important for the receiver, the degradation of the signal is, so it is expected that the filter will degrade the signal very little. The cost of the filter must be low since the budget is limited.
- A study showed that, given the position where the hubs will be located, they will have a distance range of a minimum of \( 100[\mathrm{~m}] \) and a maximum of \( 3000[\mathrm{~m}] \). The Environmental Engineering team determined that the air in CDMX, on average, has an attenuation of around \( -0.017 \mathrm{~dB} / \mathrm{m} \).
- The government has required that the system have a noise figure of no less than \( 0.80 \), although it would be desirable to have at least \( 0.90 \).
Based on your current knowledge and the information provided, determine the solution to the following problems.
1) Draw a diagram that gathers which is the communications system that is required for the implementation of the requested system. Consider for your schematic the communications system model. (10 pts)
2) Determine which sources of information will be predominant in your communications system. (5 points)
3) Indicate what type of propagation channels will be necessary for the operation of the proposed system(s). (3 pts)
4) Determine the bandwidth that your entire system will have. Also, determine the bandwidth of each of the frequency channels that make up your system. (10 pts) 5) Suppose you perform a performance test of the filter used and obtain a power measurement of \( 22.8 \mathrm{~W} \) at the cutoff frequency. Determine:
I. The maximum signal strength in this performance test. ( 5 points)
II. The attenuation that the signal would have at the input, in this performance test, with respect to the maximum power of \( 80 \mathrm{~W} \). (5 points)
III. The attenuation differential observed between the performance test and the optimal value for the filter to be used. For this point, take into account that the
