LOS ANGELES– Last year Alejandro Holcman, SVP, corporate engineering at Qualcomm, was peppered with questions surrounding the viability of millimeter wave (mmWave) spectrum as he spoke at the Mobile World Congress Los Angeles. This week, he proudly announced that many, if not most of those questions have been answered, during this year’s Light Reading breakfast event at the Mobile World Congress Los Angeles, being held this week.
“People wanted to know whether the mmWave band works for wireless technology. Is it only line of sight? What happens when you go indoors?” Holcman said. “I am really excited that we have infrastructure and real phones that use mmWaves. They are the same form factor as other mobile phones. You can do a lot with mmWave spectrum. In some cases, indoors, it is really incredible the things you can do.”
Holcman described a coverage test at Qualcomm’s headquarters in San Diego, and an mmWave site was placed pointing out toward the front door of the lobby, away from the offices, using the 28 GHz band.
“We expected significant coverage in front of the antenna,” Holcman said. “But technicians got better coverage than they expected.”
Significant coverage was experienced behind the gNodeB, including the second and third floor. The downlink median burst rate was 3.1 Gbps.
“We were very excited about how mmWave was working. We got gigabit speeds even behind the antenna because of the amount of reflections in the lobby,” Holcman said. “There are articles that say mmWave is only for line-of-sight coverage and doesn’t go around corners. But there were a lot of reflections and we got healthy coverage elsewhere in the building.”
Next, Holcman describe a coverage test in the South Hall of the Los Angeles Convention Center, where four mmWave antennas were installed to cover 350,000 square feet. Full downlink coverage was achieved with 115 dB maximum allowable path loss (MAPL). The downlink medium burst rate was 1.6 Gbps using a 400-megahertz-wide channel.
“We pretty much had full coverage, something that would be very expensive to do if you needed to isolate individual sectors in lower bands,” Holcman said. “This is the kind of capacity that mmWave is capable of providing.”
Additionally, Qualcomm has analyzed how using mmWave spectrum can provide coverage in afootball stadium with 100,000 fans uploading selfies and video and tweeting their friends. A typical stadium of that size, according to Holcman, might have a DAS with as many as 100 sectors.
“Stadiums are very expensive place to provide wireless coverage. With just 15 mmWave sites, the whole stadium was covered. The mmWave cells provide a more uniform user experience. Medium downlink throughput at all levels was more than 700 Mbps. Cell edge throughput was greater than 100 Mbps.
Another study was done in a Latin American city, where Qualcomm looked at 5G NR mmWave fixed wireless access to a 4.34 square mile dense urban area. The average building height was 39 feet and 90 percent of the buildings were less than 98 feet. Close to 90 percent coverage of the buildings was achieved with 149 LTE/5G NR mmWave small cells. The small cells used 28 GHz, 800 MHz and 100 MHz, 256X2 element antenna with beamforming, 64 QAM and 2X2 MIMO.
“We are also excited about using mmWave for fixed wireless access. It is like a replacement for fiber with a mmWave CPE on every rooftop,” Holcman said.
The progress in mmWave technology did not occur overnight. It has been a busy 12 months for Qualcomm working on mmWave technology since the last Mobile World Congress Los Angeles.
Most recently, in September, Qualcomm Technologies, introduced the Qualcomm QTM527 mmWave antenna module for the Snapdragon X55 5G Modem-RF System, delivering the a fully integrated extended-range mmWave solution for 5G fixed wireless access. This allows mobile operators to offer fixed internet broadband services to homes and businesses using their 5G network infrastructure. Before that, in August, Fujitsu Limited and Qualcomm Technologies completed non-standalone (NSA) 5G New Radio (NR) data calls on 3.7 GHz and 4.5 GHz bands and the 28 GHz band. In July, Qualcomm’s 5G NR testing facilities in Europe were expanded to include a new lab dedicated to end-to-end over-the-air (OTA) configurations for 5G NR mmWave.
Almost a year ago, Qualcomm and Nokia achieved OTA 5G NR data calls in both the mmWave and sub-6 GHz spectrum bands, which were compliant with the global 3GPP 5G NR Release 15 specification in NSA mode, using commercially available Nokia AirScale base stations, a mobile smartphone and antenna modules with integrated RF transceiver, RF front-end and antenna elements.