TY  - SER
AU  - Jang, Yong-Up
AU  - Jeong, Eui-Rim
TI  - Opportunistic Feedback and User Selection  for  Multiuser Two-Way Amplify-and- for ward Relay in Time-Varying Channels
KW  - Opportunistic Feedback
KW  - User Selection
KW  - Outage Probability
ER  -