The horizontal orientation of the transition dipole moment of the phosphorescent emitters is understood to be an important factor to enhance the external quantum efficiency (EQE) of organic light‐emitting diodes by improving light out‐coupling in optical microcavity structures. Here, red‐emitting heteroleptic iridium (III) complexes exhibiting an extremely high horizontal ratio of emitting dipole orientation (EDO) and photoluminescence quantum yield (PLQY), as well as longer device operational lifetime, without scarifying any other photophysical properties are reported. The systematic molecular design of main and ancillary ligands in heteroleptic iridium complexes leads to the achievement of both a horizontal EDO of 92% and a PLQY of 98% in the red‐emitting phosphorescent devices along with a shorter exciton decay time of 0.71 µs. Accordingly, the red‐emitting devices show excellent performances of maximum EQE of 32% and low‐efficiency roll‐off with the 1931 Commission Internationale de L′Eclariage coordinates of (0.66, 0.34). Therefore, this approach opens the way for further development of new red‐emitting iridium complexes pushing the device efficiency toward the theoretical limits.

In this paper, we design a direct radio frequency (RF) sampling receiver for multiband GNSS signals and demonstrate its performance. The direct RF sampling is a technique that does not use an analog mixer, but samples the passband signal directly, and all receiver processes are done in digital domain, whereas the conventional intermediate frequency (IF) receiver samples the IF band signals. In contrast to the IF sampling receiver, the RF sampling receiver is less complex in hardware, reconfigurable, and simultaneously converts multiband signals to digital signals with an analog-to-digital (AD) converter. The reconfigurability and simultaneous reception are very important in military applications where rapid change to other system is needed when a system is jammed by an enemy. For simultaneous reception of multiband signals, the sampling frequency should be selected with caution by considering the carrier frequencies, bandwidths, desired intermediate frequencies, and guard bands. In this paper, we select a sampling frequency and design a direct RF sampling receiver to receive multiband global navigation satellite system (GNSS) signals such as GPS L1, GLONASS G1 and G2 signals. The receiver is implemented with a commercial AD converter and software. The receiver performance is demonstrated by receiving the real signals.

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