Progress of multi-band antenna technology in mobile phone industry

Summary form only given. In the 1990´s, the mobile phone industry experienced a dramatic development. The first stage was from analog standard to digital standard development, for example, analog standard such as AMPS (advanced mobile phone system), NMT (Nordic mobile telephone) and ETACS; digital standard such as GSM, D-AMPS and CDMA. The second stage was from single band to multi-band due to the strong capacity requirements. DCS 1800 and PCS 1900 were introduced in the middle of 1990´s. Ying first proposed a dual band non-uniform helical antenna which became a popular antenna for dual band mobile phones. In the same time, P. Haapala proposed a dual band mono-helix antenna while G. Hayes proposed a meander type dual band antenna. In 1997, Ying proposed a branch multi-band antenna which has been applied into several Ericsson mobile phones. Andersson proposed a broad band shark fin antenna later. In 1998, an internal antenna was introduced to the mobile phone, which caused a lot of market interest. We started some research work in this area and soon Ying proposed an internal printed spiral antenna and a dual band printed antenna. Later in the same year, a dual band internal antenna for a mobile phone was developed. The antenna concept is based on a branched PIFA antenna. Today, many of dual band mobile handsets use this kind antenna concept. To meet the global system requirement, some so-called penta band antenna concepts are proposed. The capacitive feeding and high dielectric loading are introduced in the new concept. The multi-band technique is still a hot topic in the mobile terminal application.