1. The patents of telecom CDMA technology are all in Qualcomm's hands, including 2G CDMA 1x and 3G CDMAEVDO. Although telecom 4G is not CDMA, if you want to make a phone call or send a text message, you still need to use CDMA network. Besides producing SoC chips, another main source of profit for Qualcomm is baseband expenses. Every time a mobile phone manufacturer sells a telecom mobile phone, it has to pay a patent fee to Qualcomm. Because this fee is calculated according to the baseband, if it is a dual telecom baseband, it will give Qualcomm twice the patent fee, which greatly increases the production cost of mobile phones.
2. The 2GGSM patents used by China Mobile and China Unicom are not from Qualcomm, while the 3GTD-SCDMA and 4GTD-LTE of Mobile are independently developed by China Mobile. Although TD-LTE technology also involves some Qualcomm patents, the cost after cross-licensing is much lower than that of CDMA patents. Finally, although Qualcomm holds the patent of FDD-LTE, Qualcomm actively reduced the patent fee of FDD-LTE in order to compete with China's TD-LTE technology. Therefore, the current mobile phones of Netcom can be mobile or Unicom with dual cards at the same time. Only telecommunications can't have dual cards at the same time, because CDMA patents are too expensive.
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international standard
On April 27th, 20 17, GCF international standards organization held CAG#50 meeting in the UK, and the proposal of six-mode full netcom terminal authentication standard ("Wi-26 1: dual-card multi-standby equipment test for all modes") was passed and officially released. It marks that GCF Global Certification Laboratory began to provide "full netcom terminal certification" service to domestic and foreign terminal manufacturers.
On June 9, 20 17, GSMA International Standards Organization held its 29th plenary meeting in GSMA-TSG, Sweden, and unanimously adopted the proposal standard of adding relevant requirements for six-mode full netcom terminals in GSMA-TS.37, clearly stipulating that all netcom terminals should support LTE(TDD, FDD), WCDMA, GSM, TD-S and CDMA network standards at the same time.