3GPP (Third Generation Partnership Project) is an organization that studies and formulates specifications for mobile communication systems that handle 3rd Generation Mobile Communication Systems and subsequent LTE, LTE-Advanced, and even 5G technologies. The specifications formulated by 3GPP are widely adopted in mobile communication systems in Japan and around the world.
3GPP is a partnership project of seven Standard Development Organizations (SDOs) in various regions of the world, of which TTC is one. The seven SDOs and the regions they serve are TTC/ARIB (Japan), ATIS (North America), CCSA (China), ETSI (Europe), TSDSI (India), and TTA (Korea).
Each SDO provides its SDO members with the environment necessary for the development of 3GPP specifications and establishes standards for its country or region by referring to the 3GPP technical reports and technical specifications that have been developed, which in turn form the basis for ITU recommendations.
TTC has established a 3GPP Working Group consisting of TTC members to establish 3GPP technical reports and technical specifications as TTC standards, share information and exchange opinions on 3GPP standardization, and promote 3GPP specifications. The established TTC standards are made widely available to the public(link).