Analysis of performance parameters for wireless network using switching multiple access control method

Target scattering or reflection is used by radar systems to identify and detect targets. The larger the echo that was returned to the radar receiver, the superior the signal-to-noise ratio and the greater the likelihood of detection. The radar cross-section (RCS) determines the quantity of energy reflected from a target in radar systems. This work shows new modeling for radar targets with growing stages of fidelity. We introduce the RCS concept for straightforward point targets and extend this into additional complex states of targets with several scattering midpoints. In addition, we discuss the modeling of fluctuations in RCS with time and briefly consider the case of the polarized signal. Because the receiver and transmitter are co-located, the effort focuses on narrowband mono-static radar techniques. The RCS value changes between scans. We simulate the replicated power of a sent signal over 10,000 scanning over unit incident signals, assuming that the signal illuminates the target just once each dwell. The target is modeled by four scatterers that are placed at four square vertices. All scatterers are cylindrical-point targets on a 0.5-meter square XY plane without losing generality. The acquired results demonstrated how to generate target echoes while accounting for statistical fluctuations. From the relation between RCS and elevation angle variations for cylindrical targets, the obtained result demonstrated that the first two outputs are the same and confirmed that there is no reliance on azimuth angle. The comparison between wideband and narrowband RCS patterns demonstrated that the RCS profiles of the target-matched shallower nulls for azimuth direction are in the range of (40–50) degrees at zero elevation for 4 scatterers’ extended targets.

Section: Fig 1 a Simple Representation Of A Radar Operationmentioning

confidence: 99%

Implementation of radar cross-sections model for targets with different scattering centers

Aziez

Hamza

Al-Nuaimy

et al. 2022

“…Understanding the propagation environment is essential for evaluating wireless communication and radar systems. Applications that can benefit from developing radio frequency propagation of a radar system are given in [9,10].…”

Section: Introductionmentioning

confidence: 99%

Identifying some regularities of radio frequency propagation of a radar system by analyzing different environmental effects

Hamza

Aziez

Reja

et al. 2022

Free space path loss is a function of frequency and propagation distance and the RF signal propagates at light speed in all directions in free space. The performance evaluation of wireless and radar communication technologies is related to understanding the propagation environments. This work presents the modeling of several RF propagation properties that include atmospheric attenuation due to rain, free space path loss, gas, and fog, as well as multipath propagations caused by ground bounces. The methodology discusses the developed model according to the series of (ITU) International Telecommunication Union references to radio wave propagation. This work discusses the Free Space Path Losses (FSPL), and Propagation Losses (PL) due to the atmosphere, precipitation, snow, rain, clouds, fog, atmospheric lensing and absorption, and polarization mismatch. The work also discusses the vertical coverage diagram and radar propagation factor. The obtained results demonstrate that the PL increases with frequency and range, at a 90-degree roll angle, the attenuation approaches infinity, and as the altitude rises, the amount of attenuation caused by lensing decreases. The analysis of attenuation at 1 km vs. frequency variations, at roughly 60 GHz, indicated a high absorption owing to air gas. Lensing attenuations are also offered as secondary outputs for convenience, the wideband channels present higher performance crossways and a wide range of target height as expected. When the target height increases, the influence of multi-path fading approximately vanishes entirely due to the variation increasing in the spreading delay between the bounce and direct pathway signals. This will reduce the coherence sum between these two samples on receiving by the target

“…Accordingly, if wireless packets are sent at the same time, these data may collide at the receiver. As a result, a brief acknowledgment (ACK) packet is sent after successful packet reception [3]. Several studies discussed ALOHA random-access protocol with stochastic geometry-based modeling for investigating alternative medium access choices for LoRaWAN [4], for growing average system packets success probability (PSP) over un-slotted ALOHA [5], and in the enhanced contention resolution ALOHA scheme [6].…”

Section: Introductionmentioning

confidence: 99%

Implementation of CSMA/CA and ALOHA random-access protocols for packetizing wireless networks with model-based design

Khudor

Abdulzahra

Kudhair

2022

Because of the reliability of deployment, cost efficiency, and flexibility of ad-hoc wireless local networks (WLAN). These wireless networks have grown to be the everywhere connection solution in residential and public access networking protocols. It is important to know which strategy performs better with the least amount of delay. The Multiple Access Control protocols (MAC) that are relied on ALOHA, and Carrier Sense Multiple Access with collision avoidance (CSMA/CA) as random access techniques, have substantially aided the rapid growth of such wireless access networks. This work provides a model-based design approach for modeling CSMA/CA and ALOHA random-access protocols for packetizing wireless networks. We analyze the TX and Back-off waveforms of the PHY/MAC transceiver of three radio nodes under CSMA/CA and ALOHA operation modes and compare the obtained results of the PHY/MAC Transceiver for the network nodes according to these modes. Every node is within a range such that the communication between each couple of nodes can be interfered with and received data from the third node. The MAC layer and the logical link control function composed the data link layer. Since the same radio band is used for TX and RX, the MAC function employed here is CSMA/CA and ALOHA, which had also called a random back-off. The MAC layer sends a control signal to the TX block to transmit either a data frame or an acknowledgment frame. The frame contents are loaded in the look-up tables. The contents can be changed in the workspace. The output of this block is a complex baseband IQ signal. The obtained results show the effectiveness of CSMA/CA over ALOHA modes when comparing the corresponding Back-off waveforms and when calculating the throughput values of the three network nodes