MCX 

50 Ohm MCX sub-miniature connectors feature a snap together interface and are suitable for applications up to 6 GHz, they conform to IEC 61169-36 and CECC 22220 standards.  MCX have interface dimensions similar to SMB with a body size around 30% smaller, making them ideal for antenna and board connections where space or weight is important.  Applications include GPS, Automotive, Handheld devices, and Data Telemetry.

For details; http://www.coax-connectors.com/products/connectors/mcx.aspx