CDMA AND FH: 1. Give the 4-Ary Walsh code above, show how you construct a 8-Ary
ID: 3766105 • Letter: C
Question
CDMA AND FH:
1. Give the 4-Ary Walsh code above, show how you construct a 8-Ary Walsh Codes. Then show an example how 8 user-pairs can communicate with CDMA?
2. Using simulation and data analysis to study FHSS performance in terms of channel happing collisions.
Let’s assume there 80 channels available for frequency hopping. There are 10 users in communication concurrently for 100 seconds. Let Tc and Ts be channel hopping duration and symbol duration respectively. Tc = 200 ms and Ts < Tc.
Q.1 Write a simulation program to find out:
What is the total number of collisions for the duration of communication?
When a collision happens, the user needs to resend the message (symbol). What is the average throughput in term of symbols/second for the duration of communication?
Q2. If we let the number of users increase to 15, 20 what would your answers for the above questions?
Explanation / Answer
CDMA AND FH: 1. Give the 4-Ary Walsh code above, show how you construct a 8-Ary