A new energy consumption technique for mobile ad hoc networks

A dynamic temporary network is created through wireless mobile nodes without the need for considerable infrastructure as well as a central manager. In a mobile ad hoc network, routing protocols allow a mobile for transmission and receiving packets. In the last decade, many variants have come up for the AODV. A minimum number of hop counts are chosen for enhancing routing protocols to include additional factors that can have an impact on path selections. As the distance between each node grows, the transmission power also rises accordingly. Hence, this impacts the network’s entire performance and the most important feature is the quality of service. Most of the traditional routing protocols include energy consumption levels of the nodes and various parameters, like residual battery power, consumption of energy per packet and energy needed per transmission. A new technique is proposed in this paper to enhance the routing efficiency by making use of lion optimization algorithm after identifying all possible paths in the network. This technique not only enhances the energy efficiency of each node but also the performance metrics

A Compact Reconfigurable Dual Band-Notched Ultra-Wideband Antenna using Varactor Diodes

In this paper, a reconfigurable dual band-notched ultra-wideband (UWB) antenna is presented. The antenna design consists of a circular shape with two pairs of the L-resonator. To realize the notch characteristics in WLAN at 5.2 GHz and 5.8 GHz bands, the half wavelength of the L-resonator is introduced in the design. The T-shaped notch is etched in the ground to enhance the bandwidth which covers the UWB operating frequency range from 3.219 – 10.863 GHz. The proposed reconfigurable dual band-notched UWB antenna shows good impedance matching for the simulated in the physical layout. Furthermore, the proposed antenna has a compact size of 37.6 x 28 mm2. This proposed reconfigurable design can provide an alternative solution for the wireless system in the designing of a band-notched antenna with a good tuning capability

A Wideband Reconfigurable Folded Planar Dipole Using MEMS And Hybrid Polymeric Substrates

A wideband reconfigurable folded planar dipole using hybrid polymeric substrates is proposed. Artificial Magnetic Conductor (AMC) is a periodic structure composed of rectangular patches integrated with Jerusalem Cross (JSC) slots and being located in between two substrates. The Perfect Magnetic Conductor (PMC)-like behaviour of the AMC structure enabled the printed folded dipole to be placed near to the proposed structure, resulting in a low-profile antenna with 5.11 dB gain operating at 9.41 GHz. The combined use of the polymeric substrate and the proposed AMC resulted in a 1 GHz of bandwidth. The proposed antenna is capable in beam steering on the xz-plane via the integration of radio frequency (RF) MEMS switches placed on the antenna feeding transmission line. Simulations and measurements show a satisfactory agreement, with a beam steering capability at least 30, bandwidth of 1 GHz and maximum gain of 5.11 dB

Beam‐reconfigurable crescent array antenna with AMC plane

A beam‐reconfigurable crescent array antenna with AMC plane is presented for application at 9.41 GHz. The unit cell of the AMC plane is modeled based on a square patch integrated with rectangular ring slot with mirrored C‐shaped structures, placed between two layers of Taconic TLY‐5 substrate and located near to the main radiating element. The presented AMC design is achieved an operating bandwidth of 2.82 GHz (30%) with a center frequency of 9.41 GHz. It is found that the AMC plane can reduce the thickness of the structure in comparison to the use of a conventional ground plane, which leads to the overall compactness size of the proposed antenna of 1.1λ × 2.57λ. Moreover, through the implementation of 12 × 4 AMC unit cell, the proposed antenna improved its performance with a maximum gain and total efficiency of 10.5 dB and 97%, respectively. Meanwhile, the antenna reconfigurability is realized by integrating RF MEMS switches on its right and left arm symmetrically. The presence of a T‐shaped Yagi‐Uda‐like parasitic further widened the beam steering angle to ±63° via mutual coupling. The obtained results demonstrate a good agreement between the simulation and measurement and have a huge potential for development of X‐band radar

Dual-band aperture coupled antenna with harmonic suppression capability

The paper presents an aperture-coupled dual-band linearly-polarized antenna with harmonic suppression capability, operating at frequency 2.45 GHz and 5.00 GHz. In purpose of improving the directivity of antenna at the operating frequency of 2.45 GHz and 5.00 GHz, a modified inverted π-shaped slot-etched patch on the lower layer of the stacked antenna is introduced alongside the 50 Ω feed line. The harmonic suppression capability is achieved by the introduction of U-slot and asymmetrical left-right-handed stub at the transmission feed line, suppressing unwanted harmonic signals from 6.00 GHz up to 10.00 GHz. The final design of the antenna has produced very good reflection coefficient of -18.87 dB at 2.45 GHz and -19.57 dB at 5.00 GHz with third and higher order harmonic suppression up to -4 dB

Deep reinforcement learning with robust deep deterministic policy gradient

Recently, Deep Deterministic Policy Gradient (DDPG) is a popular deep reinforcement learning algorithms applied to continuous control problems like autonomous driving and robotics. Although DDPG can produce very good results, it has its drawbacks. DDPG can become unstable and heavily dependent on searching the correct hyperparameters for the current task. DDPG algorithm risk overestimating the Q values in the critic (value) network. The accumulation of estimation errors as time elapse can result in the reinforcement agent trapping into a local optimum or suffering from disastrous forgetting. Twin Delayed DDPG (TD3) mitigated the overestimation bias problem but might not exploit full performance due to underestimation bias. In this paper Twin Average Delayed DDPG (TAD3) is proposed for specific adaption to TD3 and shows that the resulting algorithm perform better than TD3 in a challenging continuous control environment

AMC-integrated reconfigurable beamforming folded dipole antenna with parasitic and RF MEMS

A beam-reconfigurable printed antenna on an Artificial Magnetic Conductor (AMC) is proposed for navigation and radiolocation applications at a frequency of 9.41 GHz. The AMC is formed based on a periodic Jerusalem cross shaped slot structure and is located in between two substrate layers, close to the radiator. The AMC plane has a bandwidth of 1.95 GHz around the targeted frequency of 9.41 GHz. By integrating micro-electro-mechanical system (MEMS) switches on the folded patches in combination with parasitic elements, a beam steering capability of up to ±58° is achieved with a rear full ground plane. This eliminates the need for a mechanical steering system, which is traditional in the applications targeted. The antenna achieves a high gain of 8.08 dB and 90% efficiency. A good agreement between simulated and measured results is obtained

Dual-Band Aperture Coupled Antenna With Harmonic Suppression Capability

The paper presents an aperture-coupled dual-band linearly-polarized antenna with harmonic suppression capability, operating at frequency 2.45 GHz and 5.00 GHz. In purpose of improving the directivity of antenna at the operating frequency of 2.45 GHz and 5.00 GHz, a modified inverted π-shaped slot-etched patch on the lower layer of the stacked antenna is introduced alongside the 50 Ω feed line. The harmonic suppression capability is achieved by the introduction of U-slot and asymmetrical left-right-handed stub at the transmission feed line, suppressing unwanted harmonic signals from 6.00 GHz up to 10.00 GHz. The final design of the antenna has produced very good reflection coefficient of -18.87 dB at 2.45 GHz and -19.57 dB at 5.00 GHz with third and higher order harmonic suppression up to -4 d