In this paper,a wideband true time delay line for X-band is designed to overcome the beam dispersion problem in a high-resolution spaceborne synthetic aperture radar phased array antenna system.The delay line loads th...In this paper,a wideband true time delay line for X-band is designed to overcome the beam dispersion problem in a high-resolution spaceborne synthetic aperture radar phased array antenna system.The delay line loads the electromagnetic bandgap structure on the upper surface of the substrate integrated waveguide.This is equivalent to including an additional inductance-capacitance for energy storage,which realizes the slow-wave effect.A microstrip line-SIW tapered transition structure is introduced to achieve a low loss and a large bandwidth.In the frequency band between 8-12 GHz,the measured results show that the delay multiplier of the delay line reaches 4 times,i.e.,delay line’s delay time is 4 times larger than 50Ωmicrostrip line with same length.Furthermore,the delay fluctuation,i.e.,the difference between the maximum and minimum delay as a percentage of the standard delay is only 2.5%,the insertion loss is less than-2.5 dB,and the return loss is less than-15 dB.Compared with the existing delay lines,the proposed delay line has the advantages of high delay efficiency,low delay error,wide bandwidth and low loss,which has good practical value and application prospects.展开更多
Compact antenna designs have become a critical component in the recent advancements of wireless communication technologies over the past few decades. This paper presents a self-multiplexing antenna based on diplexing ...Compact antenna designs have become a critical component in the recent advancements of wireless communication technologies over the past few decades. This paper presents a self-multiplexing antenna based on diplexing and quadruplexing Substrate-Integrated Waveguide (SIW) cavities. The diplexing structure incorporates two V-shaped slots, while the quadruplexing structure advances this concept by combining the slots to form a cross-shaped configuration within the cavity. The widths and lengths of the slots are carefully tuned to achieve variations in the respective operating frequencies without affecting the others. The proposed diplexing antenna resonates at 8.48 and 9.2 GHz, with a frequency ratio of 1.08, while the quadruplexing antenna operates at 6.9, 7.1, 7.48, and 8.2GHz. Both designs exhibit isolation levels well below –20dB and achieve a simulated peak gain of 5.6 dBi at the highest frequency, with a compact cavity area of 0.56 λg^(2). The proposed antennas operate within the NR bands (n12, n18, n26), making them suitable for modern high-speed wireless communication systems. Moreover, the properties like multiband operation, compactness, high isolation, low loss, and low interference make the antenna favorable for the high-speed railway communication systems.展开更多
基金Supported by the National Natural Science Foundation of China(61971401)。
文摘In this paper,a wideband true time delay line for X-band is designed to overcome the beam dispersion problem in a high-resolution spaceborne synthetic aperture radar phased array antenna system.The delay line loads the electromagnetic bandgap structure on the upper surface of the substrate integrated waveguide.This is equivalent to including an additional inductance-capacitance for energy storage,which realizes the slow-wave effect.A microstrip line-SIW tapered transition structure is introduced to achieve a low loss and a large bandwidth.In the frequency band between 8-12 GHz,the measured results show that the delay multiplier of the delay line reaches 4 times,i.e.,delay line’s delay time is 4 times larger than 50Ωmicrostrip line with same length.Furthermore,the delay fluctuation,i.e.,the difference between the maximum and minimum delay as a percentage of the standard delay is only 2.5%,the insertion loss is less than-2.5 dB,and the return loss is less than-15 dB.Compared with the existing delay lines,the proposed delay line has the advantages of high delay efficiency,low delay error,wide bandwidth and low loss,which has good practical value and application prospects.
文摘Compact antenna designs have become a critical component in the recent advancements of wireless communication technologies over the past few decades. This paper presents a self-multiplexing antenna based on diplexing and quadruplexing Substrate-Integrated Waveguide (SIW) cavities. The diplexing structure incorporates two V-shaped slots, while the quadruplexing structure advances this concept by combining the slots to form a cross-shaped configuration within the cavity. The widths and lengths of the slots are carefully tuned to achieve variations in the respective operating frequencies without affecting the others. The proposed diplexing antenna resonates at 8.48 and 9.2 GHz, with a frequency ratio of 1.08, while the quadruplexing antenna operates at 6.9, 7.1, 7.48, and 8.2GHz. Both designs exhibit isolation levels well below –20dB and achieve a simulated peak gain of 5.6 dBi at the highest frequency, with a compact cavity area of 0.56 λg^(2). The proposed antennas operate within the NR bands (n12, n18, n26), making them suitable for modern high-speed wireless communication systems. Moreover, the properties like multiband operation, compactness, high isolation, low loss, and low interference make the antenna favorable for the high-speed railway communication systems.
