TY - JOUR
T1 - Co-circularly polarized planar antenna with highly decoupled ports for S-band full duplex applications
AU - Nawaz, Haq
AU - Niazi, Ahmad Umar
AU - Tahir, Ahsen
AU - Ahmad, Noman
AU - Masud, Usman
AU - Althobaiti, Turke
AU - Alotaibi, Abdullah Alhumaidi
AU - Ramzan, Naeem
PY - 2022/2/2
Y1 - 2022/2/2
N2 - This work presents a unidirectional, co-circularly polarized (CP), printed antenna with highly decoupled or isolated transmit (Tx) and receive (Rx) ports for 2.4 GHz in-band full duplex (IBFD) applications. The presented antenna topology is based on four similar and sequentially rotated trimmed patches with right hand circular polarized (RHCP) characteristics. The symmetrical placement of two Tx patches with respect to both Rx elements results in equal levels of self interference (SI) which was suppressed through balanced excitation of Tx mode. This mechanism results in effective suppression of SI at each Rx patch. The residual SI is suppressed further through a second balanced feeding network deployed at Rx port of proposed antenna topology. The employed balanced feeding networks provide superior performance of ≤ 0.5 dB and 6° magnitude and phase imbalances respectively between the two balanced output ports over the bandwidth of interest. The measured results for prototype of presented antenna achieve -10 dB bandwidth of better than 100 MHz for both Tx and Rx ports. The measured interport coupling for validation model ≤ -70 dB across the entire bandwidth of 100 MHz. As per best of authors’ knowledge, the presented antenna is the first one to report such reduced levels of interport coupling over the whole impedance bandwidth of planar antenna with unidirectional radiation patterns and co-RHCP characteristics for both Tx and Rx modes across the overlapped bandwidth.
AB - This work presents a unidirectional, co-circularly polarized (CP), printed antenna with highly decoupled or isolated transmit (Tx) and receive (Rx) ports for 2.4 GHz in-band full duplex (IBFD) applications. The presented antenna topology is based on four similar and sequentially rotated trimmed patches with right hand circular polarized (RHCP) characteristics. The symmetrical placement of two Tx patches with respect to both Rx elements results in equal levels of self interference (SI) which was suppressed through balanced excitation of Tx mode. This mechanism results in effective suppression of SI at each Rx patch. The residual SI is suppressed further through a second balanced feeding network deployed at Rx port of proposed antenna topology. The employed balanced feeding networks provide superior performance of ≤ 0.5 dB and 6° magnitude and phase imbalances respectively between the two balanced output ports over the bandwidth of interest. The measured results for prototype of presented antenna achieve -10 dB bandwidth of better than 100 MHz for both Tx and Rx ports. The measured interport coupling for validation model ≤ -70 dB across the entire bandwidth of 100 MHz. As per best of authors’ knowledge, the presented antenna is the first one to report such reduced levels of interport coupling over the whole impedance bandwidth of planar antenna with unidirectional radiation patterns and co-RHCP characteristics for both Tx and Rx modes across the overlapped bandwidth.
KW - circularly polarized antenna
KW - undirectional radiation pattern
KW - reduced interport coupling
KW - self interference suppression
KW - balanced feeding network
U2 - 10.1109/ACCESS.2022.3148740
DO - 10.1109/ACCESS.2022.3148740
M3 - Article
SN - 2169-3536
VL - 10
SP - 16101
EP - 16110
JO - IEEE Access
JF - IEEE Access
ER -