8. (15 pts) In an CDMA coding scheme shown below, there are two senders using two spreading codes. First, prove that the two spreading codes of sender 1 and sender 2 are orthogonal, and show your calculation process. Secondly, please show how to calculate receiver 2's received data, and then verify whether it is the same data sent by sender 2. senders data bits channel sums together transmissions by sender! and 2 Sender channel, zin .m Code ODDI data Sender 2 bits code Z = d.ca um NO slot 1 slot 0 received received input input using same code as sender I, receiver recovers sender I's original data receiver 1 from summed channel data