22 research outputs found
A wideband F-shaped patch antenna for S-band CubeSats communications
A wideband S-band F-shaped patch antenna is proposed for CubeSats communications. To broaden bandwidth, it uses two arms with different lengths to generate a second resonant frequency. The effect of the arm length and width on the return loss, resonant frequency and impedance bandwidth on a 3U CubeSat is studied. The simulation results show that the antenna achieves a wideband of 1121 MHz (1.606-2.727 GHz) with a return loss below ā10 dB over the entire frequency band from 1.606 to 2.727 GHz. The antenna has a high gain of 8.51 dB and a small return loss of ā32.85 dB at 2.45 GHz
Telemetry, tracking and command subsystem for LibyaSat-1
In this paper we present the design and the analysis of Telemetry, Tracking and Command Subsystem (TT&CS) for Libyan imaging mini-satellite (LibyaSat-1). This subsystem is the brain and the operating system of any satellite or spacecraft as it performs three important functions; tracking mini-satellite position, monitoring mini-satellite health and status and processing received and transmitted data. Moreover, the uplink and downlink budgets for s-band and x-band antennas are presented. We also designed s-band C-shaped patch antenna for command receiver (2.039 GHz). Electromagnetic simulation was performed to this antenna High Frequency Structure Simulator (HFSS). Our results show that the s-band C-shaped patch antenna achieves high gain of 6.45 dB and wide bandwidth; i.e., 1500 MHz. The achieved simulated return loss is -19.6 dB at a resonant frequency of 2.039 GHz
S-band Planar Antennas for a CubeSat
This paper studies the suitability of shorted patch and CPW-feed square slot antennas for CubeSat communications. To study the effect of the CubeSat body on the antennas performance, we have simulated both antennas in the High Frequency Structure Simulator (HFSS) with and without the CubeSat body. Compared to CPWfeed square slot antenna, the shorted patch antenna achieves higher gain and wider bandwidth. We have also re-dimensioned both antennas to shift their resonant frequencies to 2.45 GHz using Quasi Newton method in HFSS. This thus enables their use in the unlicensed ISM band. The repurposed shorted patch has smaller return loss; e.g., -27.5 dB (without CubeSat), higher gain; e.g., 5.3 dBi and wider bandwidth than the repurposed CPW-feed Square slot antenna. Lastly, further enhancement in the gain of re-dimensioned CPW-feed square slot antenna shows an increase of total gain from 2 to 2.52 dB
A survey and study of planar antennas for pico-satellites
Works on pico-satellites have gained momentum recently, especially those that consider pico-satellites as part of a much larger constellation or swarm. This feature allows pico-satellites to provide high temporal resolution of observational data and redundancy. In particular, it reduces the need for satellite-to-ground communications and, hence, helps save energy and allows the execution of distributed processing algorithms on the satellites themselves. Consequently, satellite-to-satellite or cross-link communication is critical. To realize these advantages, the cross-link antenna employed on pico-satellites must meet many criteria, namely, small size, lightweight, low-power consumption, high gain, wide bandwidth, circular polarization, and beam steerability. To date, no works have examined the suitability of existing planar antenna designs for the use on pico-satellites. To this end, this paper contributes to the literature by focusing on microstrip patch and slot antennas that have the ability to achieve high gain, beam steering, and wide bandwidth. This paper reviews 66 planar antenna designs, which includes 38-patch and 28-slot antennas. In addition, we provide an extensive qualitative comparison of these antennas in terms of their mass, size, gain, beam steerability, type of polarization, operating frequency band, and return loss. In addition, we have evaluated three antenna designs that best address the pico-satellite challenges on a common platform. We find that the asymmetric E-shaped patch antenna design is the most suitable for the use on 2U CubeSats. This is because of its small size ( mm and high gain (7.3 dB). In addition, the E-shaped patch antenna yields a wide ā10-dB bandwidth of 2300 MHz and a small return loss of ā15.2 dB
A Printed Yagi Antenna for CubeSat with Multi-Frequency Tilt Operation
In this paper, a printed Yagi antenna with an integrated balun is proposed for CubeSat communications. The printed antenna is mechanically adjustable to realize three functional states at different operating frequencies in the Lāband and Sāband respectively. Three different angle deployments are proposed at 10Ā°, 50Ā° and 90Ā°, so that the antenna operates at three different operating frequencies, namely 1.3 GHz (Lāband), 2.4 GHz (Sāband) and 3 GHz (Sāband). The measured results of the fabricated antenna are well matched with the simulation, having frequencies of 2.82ā3.07 GHz, 1.3ā1.4 GHz and 2.38ā2.57 GHz, with similar radiation patterns. The measured gain of the antenna is 8.167 dBi at 2.4 GHz, 5.278 dBi at 1.3 GHz and 6.120 dBi at 3 GHz. Keeping within the general theme of cheap off the shelf components for CubeSats, this antenna design allows the CubeSat designers to choose from three popular frequencies, through a simple angle configuration. The main contribution of this work lies with the reconfigurable frequency, relatively high gain and simplicity of design
Dipole antenna array cluster for CubeSats
CubeSats are attracting interest from both the industry and academia because of their affordability. Specifically, they are made from commercial Off-The-Shelf (COTS) electronic circuit chips, and are thus seen as a cost effective replacement for traditional, expensive satellites. Moreover, they are expected to have higher capabilities to better support demanding missions. To date, most CubeSats rely on a single element antenna that usually has a relatively low gain and are not steerable. Thus, they are not suitable for long-distance communications and for use by missions requiring high-speed links and adjustable radiation patterns. Existing single element antennas also increase the probability of failure when establishing communication links, as the failure of the single element would lead to a disconnection. In this paper, we propose a 3x1 dipole antenna array and a cluster of three 3x1 dipole antenna arrays for CubeSats. Each array can theoretically be used on a separate frequency. Advantageously, all three arrays can be combined to enhance directivity. Our simulation results show that the proposed antenna cluster has a high gain of 5.03dB and wide directivity
Printed Yagi-Uda antenna array on CubeSat
CubeSats are now becoming increasingly popular for space programs. This is because of their affordability. Moreover, CubeSats can be built using commercial Off-the Shelf (COTS) components. They are cost effective compared with traditional satellites. CubeSats can communicate with each other within a swarm, and with ground station. These capabilities require CubeSats to be equipped with small antennas to facilitate cross-link or downlink communications. Therefore, in this paper, we present a novel design of high gain printed Yagi-Uda antenna and a two element Yagi-Uda antenna array which can be perfectly attached on 3U CubeSat\u27s aluminum bodies to avoid deployment. We have shown a numerical analysis of Yagi antenna array and simulated the antenna using the High Frequency Simulator Structure (HFSS). The simulation model is completed with the existing of CubeSat mental body. Our results show that the antenna array achieves good impedance matching with a return loss of-26.47 dB at the desired frequency of 2.47 GHz, a-10dB impedance bandwidth of 134 MHz (2.396-2.530 GHz) and has a total gain of 6.41dB
A low profile high gain CPW-fed slot antenna with a cavity backed reflector for CubeSats
A low profile, high gain, CPW-fed, slot antenna is proposed for CubeSats. The proposed antenna is backed with a low profile metallic reflector. The cavity reflector is utilized to significantly improve gain and reduce back lobe radiation. The antenna has a compact size of 36x36 mm 2 , meaning it is compatible with any CubeSats standard structure. We have simulated the antenna on a 2U CubeSat (10cmx10cmx20cm). Our results show that the antenna achieves good impedance matching with a return loss of-30 dB at the desired frequency of 2.45 GHz, a-10-dB impedance bandwidth of 109 MHz (2.391-2.50 GHz) and has a total gain of 8.62 dB
A wideband C-shaped patch antenna for LibyaSat-1
This paper presents a wideband C-shaped patch antenna for LibyaSat-1. The two parallel slots of the upper C-shaped path are incorporated to generate a second resonant frequency and hence broaden bandwidth. The folded patch technique is used to reduce the coaxial probe length and inductance at the feed section. In addition, the Quasi Newton method is used to achieve an operating frequency of 2.215 GHz (S-band). Our simulation results show that the antenna achieves a -10-dB impedance bandwidth of 1550 MHz (2.00-3.55 GHz), and has a total gain of 6.45 dB at 2.215GHz
Novel DTN Mobility-Driven Routing in Autonomous Drone Logistics Networks
Drones have become prevalent for the delivery of goods by many retail companies such as Amazon and Dominos. Amazon has an issued patent that describes how drones scan and collect data on their fly-overs while dropping off packages. In this context, we propose a path optimization algorithm for a drone multi-hop communications network that can carry and forward data in addition to its primary function of parcel deliveries. We argue that traditional Delay Tolerant Networking (DTN) based protocols may not be efficient for this purpose. Therefore, this paper proposes a new DTN-based algorithm that optimizes drone flight paths in conjunction with optimized routing to deliver both parcels and data in a power efficient way and within the shortest possible time. We propose a heuristic algorithm called Weighted Flight Path Planning (WFPP) that priorities the data packets in an exchange pool in order to create an optimized path for the drones. Our approach is to determine a weight for each packet based on the packet\u27s remaining time to live, priority, size, and location of the packet\u27s destination. When two drones meet each other, they exchange the high weighted packets. Simulation studies show that WFPP delivers up to 25% more packets compared with EBR, EPIDEMIC, and a similar path planning method. Also, WFPP reduces the data delivery delays by up to 66% while the overhead ratio is low