Multi‐frequency characteristics of annular‐ring slot antennas

Abstract

The intensity-temporal profiles of the converted S1 wave (at the fiber output end) and the control P1 wave (at the fiber input end) are demonstrated in Figure 3 (P1 is 10 Gb/s) and 4 (P1 is 20 Gb/s) to show the pulse properties and conversion feasibility in the dispersion region. It can be seen that the information (intensity and phase profiles) of P1 is imprinted on the S1 wave. Although the conversion efficiency will decrease as the bit rate increases, the decrease in our model can be compensated by the Raman amplifications from S2 and P2 waves. Clearly, the width of pulses will be broadened because of the dispersion effects, and also will broaden further at a higher repetition rate. The distortion of the profile and overlap of the pulse will occur if higher bit rates are used. CONCLUSIONA novel wavelength conversion scheme, based on the groupvelocity matched fiber Raman-resonant FWM, has been proposed where we can use a long fiber (L ϭ 500 m) in the converter and employ a high-power laser diode. With the appropriate arrangement of pump and Stokes waves in the polarization-preserving birefringent fibers, we have presented a novel simulation model and numerically demonstrated the power and temporal evolutions of the converted and pump signals. The results of pulse broadening and conversion efficiency have also been discussed. The scheme is compact and practical for use in flexible and reconfigurable wavelength-reuse networks. MULTI-FREQUENCY CHARACTERISTICS OF ANNULAR-RING SLOT ANTENNAS

Design of dual‐band annular slot antenna with strip‐loaded approach

“…Additionally, the printed antennas must cover multiband to support multi-standard services, because communication bands vary with area or country. A survey of the literature indicates that the printed slot antenna is a promising candidate for implementing the wideband or multiband standards with a small area [1][2][3][4][5][6][7][8]. Several design approaches and implementations have been demonstrated to fulfill the desired dual-band requirements.…”

Design and Investigation of a Dual-Band Annular Ring Slot Antenna for Aircraft Applications

“…In recent years, many annular ring slot antennas have been developed for dual-frequency operations [1][2][3][4][5][6][7][8][9][10][11][12][13], and several of methods have been used to create antenna with dual-band characteristic. One of the typical methods is to introduce another concentric annular-ring slot [1][2][3][4][5][6].…”

“…One of the typical methods is to introduce another concentric annular-ring slot [1][2][3][4][5][6]. However, in order to obtain the dual-band input impedance matching, some other structures should be embedded into the antenna, such as circular photonic bandgap (PBG) structures [3], tree-shaped coupling strip with branches [5] and a cross-slot [6].…”

Design of a Compact Dual-Band Annular-Ring Slot Antenna

“…Some PSAs were designed to generate circularly polarized waves with desired handed senses [1][2][3]; some were further enhanced in their bandwidths [4][5][6]; others were developed to support dualband operations [7][8][9][10][11][12][13][14][15][16][17]. For those microstrip-line-fed PSAs designed for dual-band operations, many of them are designed to cover the 2.4/5 GHz wireless local-area network (WLAN) bands.…”

“…For those microstrip-line-fed PSAs designed for dual-band operations, many of them are designed to cover the 2.4/5 GHz wireless local-area network (WLAN) bands. In the past, different frequency bands of a PSA were produced by implementing disjoint slot lines [7,8], by designing a novel feeding structure [9,10], or by embedding in the slot a metallic patch or strip [11][12][13]. Although simple in structure, these antennas, inclusive of the ground planes, are still relatively large.…”