Integrated Wideband Self-Interference Cancellation in the RF Domain for FDD and Full-Duplex Wireless

A 24 GHz Waveguide based Radar System using an Advanced Algorithm for I/Q Offset Cancelation

“…This leads to an optimized usage of the dynamic range of the analog-to-digital converters if the adjusted baseband signal pairs are differentially sampled and appropriately amplified. Similar approaches were published in (Zhou et al, 2015) to cancel transmitter self-interference in the RF domain for frequency-division duplexing and full-duplex wireless applications and in (Boaventura et al, 2016) to suppress RF self-jamming in passive radio-frequency identification (RFID) systems. Since an I/Q offset cancelation also simplifies blind I/Q regeneration (Mailand and Richter, 2005), the proposed system concept can also be adapted and utilized for optimizing Six-Port based quadrature amplitude modulation (QAM) receivers.…”

Performance Limitations Analysis of Imperfect Attenuators for Adaptive Self-Interference Cancellation Systém

“…Generally, the adaptive interference cancellation system is consisted of a sample coupler, delay unit, phase shifter, two attenuators, delay estimation devices, attenuation values calculation devices and cancellation coupler [2], [3], [7], which is shown in Fig. 1.…”

“…In the last decades, researchers have made great contributions to the adaptive interference cancellation system (AICS) [2][3][4][5][6][7][8][9][10], and these studies are focused on not only military application but also civil communication systems. [2] employs a RF adaptive self-interference cancellation system (RFAICS) based on controlling and mixing two orthogonal signals derived from transmitted signal, and improves the power handling capability of signal controller.…”

“…The self-interference of communication sites containing frequency hopping (FH) and single channel radios is analyzed in [4]. Furthermore, AICS is also applied in electrocardiography to cancel interference [5], and RFAICS is also the critical self-interference suppression method for civil co-time and co-frequency full-duplex communication systems [6][7][8]. On the whole, the adaptive cancellation methods of above literatures are all based on minimum mean square error (MMSE) criterion.…”

Tunable Frequency-Division Duplex RF Front End Using Electrical Balance and Active Cancellation

“…Conversely, passive SIC can cancel Tx noise, but wideband cancellation requires high RF complexity. Passive feedforward cancellation requires adaptive multi-tap analog filters [24], [25]. Similarly, in EBDs, the isolation bandwidth is limited by frequency domain variation in the antenna and balancing reflection coefficients, and therefore providing isolation in both bands entails increased RF complexity in the balancing network [18], [20], [27], [28].…”