Description
Q1.
The distance between cell centers with the same frequency band is required to be more than 6 km. What is the cell radius for the cluster size of 12.
Q2.
Using the NxSxK notation, label the frequency re-use patterns below:
(a)
(b)
(c)
(d)
Q3.
Consider a cluster size of 7 for fractional frequency re-use in hexagonal cellular networks. Assume that each cell is allocated an identical set of 7 frequencies, F1 to F7, to be used within the cell. Draw a cluster of 7 cells showing the frequency use in the centers and borders of the cells.
Q4.
A particular cellular system has the following characteristics: cluster size =9, uniform cell size, user density=100 users/sq km, allocated frequency spectrum = 900-945 MHz, bit rate required per user = 10 kbps uplink and 10 kbps downlink, and modulation code rate = 2 bps/Hz. Answer the following questions.
- Using FDMA/FDD:
- How much bandwidth is available per cell using FDD?
- How many users per cell can be supported using FDMA?
- What is the cell area
- What is the cell radius assuming circular cells?
- If the available spectrum is divided in to 100 channels and TDMA is employed within each channel:
- What is the bandwidth and data rate per channel?
- How many time slots are needed in a TDMA frame to support the required number of users?
- If the TDMA frame is 10ms, how long is each user slot in the frame?
- How many bits are transmitted in each time slot?
End of homework
