5G cellular connectivity isn't an if, but a when. The next generation of mobile wireless promises much higher peak download speeds than today's LTE deployments, but to get there, carriers will need to deploy ample base stations covering the 28-GHz band, more commonly known as mmWave. mmWave signals are short-ranged, directional, and easily attenuated, so it's difficult to maintain a consistent connection with a mobile device using that spectrum. Despite those challenges, mmWave is a holy grail of sorts for 5G because bandwidth in that spectrum is abundant and can be used to carry lots of data quickly.
Counter-clockwise: the QTM052 mmWave module, the Snapdragon X50 modem, and a U.S. penny
Qualcomm thinks it has an answer to the problems of mobile mmWave with its QTM052 family of antenna modules. The company says it's miniaturized the components of each 5G antenna and RF front-end into a single tiny integrated package. Despite the fact that each of these modules has to use multiple phased antennas in concert to perform the beam-forming, beam-steering, and beam-tracking required for practical communications in the 28-GHz band, each QTM052 is small enough to fit on the first segment of an index finger.
That small size means the QTM052 module can go in the side bezel of a smartphone, making 28-GHz-band 5G transmission practical in today's wafer-like handsets. While Qualcomm has demonstrated a working 28-GHz-band antenna in the past, the company says that unit was still too large to be useful for the kinds of devices phone makers will want to be making as 5G rolls out in the 2019-to-2020 time frame.
Up to four QTM052 modules can go into a 5G phone alongside Qualcomm's Snapdragon X50 5G NR modem. The X50 conducts the entire mmWave orchestra by constantly tracking the signal strength of each beam available to the QTM052s and picking the strongest one for communication. In the event the modem's preferred beam is blocked, Qualcomm says the X50 can quickly pick from alternate signals available to it and seamlessly continue transmitting. Environmental obstacles aside, using multiple QTM052 modules in a device could mean that if a user blocks one or more transceivers with their hand, at least one other module will still have a clear path to the base station.
To drive home the point of just how important the QTM052 is to the mobile 5G future, Qualcomm pointed out that Intel's concept 5G PC, shown at MWC earlier this year, relied on two chunky fold-out kickstands in order to house its 5G modules. It's worth remembering that Intel's 5G concept isn't representative of production devices, but the blue team also hasn't shown advances similar to Qualcomm's in 5G RF modules just yet. Instead, the company is focusing more on 5G infrastructure and experience its 5G technologies might provide to users.
mmWave is just one half of 5G connectivity, in any case. Qualcomm itself notes that 28 GHz signals will be most commonly found in urban and indoor environments. For broader 5G coverage in the hills and dales, handset makers will need to integrate radios that talk in the sub-6-GHz bands. Qualcomm's QPM5650, QPM5651, QDM5650, and QDM5652 modules will handle that lower-frequency grunt work in future devices.
Each QPM module has an integrated 5G NR-compatible power-amp, low-noise amp (LNA), switch, and filtering subsystem inside, while the QDM5650 and QDM5652 have integrated LNAs and switches for diversity and MIMO. Qualcomm says both families of module have integrated sounding reference signal, or SRS, switching on board to help support the “massive MIMO” required of 5G NR devices.
The QTM052 mmWave antenna module and the QPM56xx RF modules are sampling to Qualcomm's customers now.