Full-screen handsets with edge-to-edge displays and screen aspect ratios of 18:9 are now being introduced by smartphone manufacturers. However, these features also come with their own set of RF-related challenges. Specifically, the space available for antennas is reduced, potentially causing problems like shorter battery life, connectivity issues, and lower data rates. In the white paper “Overcoming the RF Challenges of Full-Screen Smartphones,” Qorvo explores the topic of enabling next-generation handset designs without sacrificing RF performance.
Smartphone manufacturers are transitioning to full-screen designs—i.e., displays that occupy nearly the entire face of the smartphone. Hence, less space is available for antennas, which must be located outside the area occupied by the screen. And with phones becoming narrower with the shift to 18:9 screen aspect ratios, antennas must be shorter. In addition, the number of antennas required in a smartphone is increasing, as more antennas are needed to deliver higher data rates using various approaches.
Reduced antenna area and length both can impact antenna performance. Specifically, reduced antenna area decreases antenna efficiency. Bandwidth is also reduced, making it more difficult to optimize efficiency at specific bands. The white paper notes the consequences of affected antenna performance, as potential problems include shorter battery life, poor connections, reduced operating range, and lower data rates.
Lower antenna efficiency and bandwidth affect key transmit (Tx) and receive (Rx) RF performance metrics like total radiated power (TRP) and Rx sensitivity. To compensate for these effects, increased performance is required throughout the Tx and Rx paths within the RF front end (RFFE). The white paper explains that integrated modules are important for achieving these performance improvements.
The white paper discusses approaches engineers can take to address full-screen design challenges. One of them is increasing TRP, which requires maximizing the performance of components in the Tx path. Such components include power amplifiers (PAs), filters, and antenna tuners. Increasing Rx sensitivity, which is another point mentioned, can be achieved by utilizing high-performance components like antenna-tuning solutions, low-loss filters and duplexers, and low-noise amplifiers (LNAs).
Qorvo Inc., 7628 Thorndike Rd., Greensboro, NC 27409; (336) 664-1233