An anonymous reader quotes a report from Mac Rumors: With the iPhone 7 and the iPhone 7 Plus, Apple elected to use LTE modems from two different sources, Qualcomm and Intel. The A1778 and A1784 iPhone models use a GSM-only Intel XMM7360 modem while the A1660 and 1661 iPhone models use a GSM/CDMA-compatible Qualcomm MDM9645M modem. Apple’s decision has already caused some disappointment among customers because the GSM-only Intel modem is not compatible with as many carrier networks as the GSM/CDMA Qualcomm modem, and now independent testing conducted by Cellular Insights suggests there are some significant performance differences between the two modems, with the Qualcomm modem outperforming the Intel modem. Using an RS TS7124 RF Shielded Box, two RS CMW500, one RS CMWC controller, and four Vivaldi antennas, Cellular Insights created a setup to simulate LTE performance at different distances from a cellular tower using two iPhone 7 Plus devices, one with an Intel modem and one with a Qualcomm modem. The goal of the test was to measure the highest achievable LTE throughput starting at a Reference Signal Received Quality of -85dBm (a strong signal) and gradually reducing the power level to simulate moving away from a cellular tower where signal is weaker. Three LTE bands were tested: Band 12, Band 4 (the most common band in North America), and Band 7. In all three tests, both the iPhone 7 Plus models offered similar performance in ideal conditions, but as power levels decreased, Cellular Insights saw “unexplainable sharp dips in performance” in the Intel modem, finding a gap “north of 30%” in favor of the Qualcomm iPhone 7 Plus. In the charts, the Qualcomm modem maintains noticeably higher throughput speeds than the Intel modem as signal strength decreases. According to Cellular Insights, in every single test, the iPhone 7 Plus with a Qualcomm modem “had a significant performance edge” over the iPhone 7 Plus with an Intel modem.
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