[IEEE 2013 IEEE MTT-S International Microwave Workshop Series on RF and Wireless Technologies for Biomedical and Healthcare Applications (IMWS-BIO) - Singapore, Singapore (2013.12.9-2013.12.11)] 2013 IEEE MTT-S International Microwave Workshop Series on RF and Wireless Technologies for Biomedical and Healthcare Applications (IMWS-BIO) - Cross slot antenna with very low back radiation for various wireless communications at 5.8GHz ISM band