Multiple-antenna radio frequency (RF) transceivers offer numerous advantages over single-antenna transceivers. In addition, digital beamforming is becoming preferred for RF wireless signal transmission and reception because of the ability to form and steer multiple simultaneous beams, ease of digital array calibration, and support for multi-in-multi-out (MIMO) capabilities. However, current digital beamforming receiver arrays lack RF/analog spatial interference rejection and thus require analog-to-digital converters (ADC) to have a very high dynamic range to tolerate RF interference, which increases power dissipation. This technology presents a scalable four-element MIMO receiver array that combines the benefits of digital beamforming and spatial RF interference suppression by integrating spatial notch filters and tunable RF spectral bandpass filters. This technology can therefore alleviate the requirement for high ADC dynamic range and presents a power-efficient and reliable digital beamforming MIMO receiver array for next generation wireless communications.
When receiving a wireless signal with a multiple-antenna receiver, unwanted signals may be received at various incident angles at various unwanted RF frequencies. For digital beamforming arrays that lack RF interference suppression capabilities, the ADC that converts the received analog signals to digital signals may saturate if the unwanted signals are stronger than the desired ones, rendering it incapable of processing the latter signals. This technology adds a steerable spatial notch filter and a tunable spectral RF filter that can suppress unwanted signals at specific incident angles and frequencies, so that the unwanted signals do not saturate the ADC. Therefore, this technology can enable power efficient and high data-rate digital beamforming MIMO receiver arrays.
A prototype of the technology has been tested and been shown to effectively form multiple digital beams for MIMO applications, as well as spatially and spectrally reject RF/analog interference.
Tech Ventures Reference: IR CU16169