In this paper, we present the design, development and implementation of an integrated system for ... more In this paper, we present the design, development and implementation of an integrated system for the management of COVID-19 patient, using the LoRaWAN communication infrastructure. Our system offers certain advantages when compared to other similar solutions, allowing remote symptom and health monitoring that can be applied to isolated or quarantined people, without any external interaction with the patient. The IoT wearable device can monitor parameters of health condition like pulse, blood oxygen saturation, and body temperature, as well as the current location. To test the performance of the proposed system, two persons under quarantine were monitored, for a complete 14-day standard quarantine time interval. Based on the data transmitted to the monitoring center, the medical staff decided, after several days of monitoring, when the measured values were outside of the normal parameters, to do an RT-PCR test for one of the two persons, confirming the SARS-CoV2 virus infection. We h...
Energy management efficiency is a topical issue for Internet of Things (IoT) sensor networks beca... more Energy management efficiency is a topical issue for Internet of Things (IoT) sensor networks because a sensor can be placed in harsh or hardly accessible places and must transmit data without maintenance. One characteristic of the LoRa technology is the high current peaks during the data transmission procedure. These current peaks can decrease the lifetime of the conventional power sources. Thus, to protect the conventional battery of the wireless sensor from degradation during fast discharging, a hybrid energy storage system can help. This article presents the design and development of a LoRaWAN sensor powered by a hybrid energy storage system and an energy management solution that can be integrated into the node. The novel solution presented integrates a 330-mW photovoltaic (PV) panel as a main source, a 4-F supercapacitor and a 230-mA small form factor Lithium battery as backup and it was tested in a real IoT application. Currently, as the most used solution to increase the battery lifetime of a LoRaWAN sensor is to reduce the communication time with the Gateway, our hybrid power management system comes with a solution for the node to be powered for a very long period of more than two years in worst case scenario configuration when the PV panel is not installed and more than ten years with hybrid power solution, without the compromise of reducing the communication time. The achieved communication distance is about 580 m with SF7 and more of 2 km with SF12 in an urban area.
This article presents a novel visible light communications receiver architecture, designed for au... more This article presents a novel visible light communications receiver architecture, designed for automotive applications. A central problematic in this area is the design of a suitable receiver able to face the problems caused by the dynamic situations, by the long distances and also by the environmental conditions. In such circumstances, a solution would be to adapt the communication's data rate to channel conditions, meaning that the communication would take place using different data rates depending on the signal to noise ratio (SNR) and the message priority. Considering the digital filtering better performances, the proposed architecture considers the usage of digital signal processing (DSP) as an alternative to the analog signal treatment. The visible light communication receiver proposed in this article addresses the upper mentioned issues and enables a robust communication even at low SNR.
This paper proposes an implementation of access control gates in a distributed administration sys... more This paper proposes an implementation of access control gates in a distributed administration system, based on RFID technologies (RFID tags). Within this administration system, we emphasize the independent stations controlling the access through different gates, as well as the architectures of the involved hardware and software part.
2015 International Symposium on Signals, Circuits and Systems (ISSCS), 2015
This paper presents a low cost and a low profile flexible microstrip patch tag antenna for UHF RF... more This paper presents a low cost and a low profile flexible microstrip patch tag antenna for UHF RFID systems that can be metal mountable. The simple design that doesn't imply using shorting pins, flexibility and small size (25mm × 50mm × 0.5mm) are a few of the advantages given by this design. The proposed antenna is simulated and the results obtained are compared with measurements performed with Agilent FieldFox N9912A VNA. At ETSI frequency band, the reading distance is up to 2.7m, which shows that the tag achieves good size/performance ratio for flexible metal mountable UHF RFID tags. The gain of the antenna is only -16.25dB, but in order to reach the mentioned reading distance is used an RFID chip having a wake-up power of -20.5dBm. The proposed tag can be easily mounted on metallic objects having various sizes and shapes.
Many efforts where made in the last years in order to develop new techniques for mobile objects i... more Many efforts where made in the last years in order to develop new techniques for mobile objects identification, location and tracking. Radio Frequency Identification (RFID) systems are a possible solution to this problem. There are many different practical implementations of such systems, based on the use of radio waves from low frequencies to high frequencies. In this paper we present a short review of existing RFID systems, and an in depth analysis of one commercial system, the RFID RADAR. The results are from experiments performed in real life conditions. Also, this paper offers important EMC information regarding the use of high frequency RFID system.
Reading RFID tags positioned at different angles is an important aspect especially if exists a me... more Reading RFID tags positioned at different angles is an important aspect especially if exists a metallic environments influence over the reader antenna. In this paper is proposed one successfully solution of the problem generated by presence of metallic environments ...
Abstract: In this paper we present an evaluation of location systems available commercially on th... more Abstract: In this paper we present an evaluation of location systems available commercially on the world market as full working systems or as prototype and evaluation versions. We made tests for both location precision and electromagnetic field emissions in order to find out the ...
The digital revolution has changed the way we implement and use connected devices and systems by ... more The digital revolution has changed the way we implement and use connected devices and systems by offering Internet communication capabilities to simple objects around us. The growth of information technologies, together with the concept of the Internet of Things (IoT), exponentially amplified the connectivity capabilities of devices. Up to this moment, the Long Range (LoRa) communication technology has been regarded as the perfect candidate, created to solve the issues of the IoT concept, such as scalability and the possibility of integrating a large number of sensors. The goal of this paper is to present an analysis of the communication collisions that occur through the evaluation of performance level in various scenarios for the LoRa technology. The first part addresses an empirical evaluation and the second part presents the development and validation of a LoRa traffic generator. The findings suggest that even if the packet payload increases, the communication resistance to inter...
The paper summarizes our preliminary findings regarding the development and implementation of a n... more The paper summarizes our preliminary findings regarding the development and implementation of a newly proposed system based on ICT and RFID (Radio Frequency Identification) technologies for campus access and facility usage. It is generally acknowledged that any educational environment is highly dependent upon a wide range of resources or variables such as teaching staff, research and study areas, meeting and accommodation facilities, library services, restaurant and leisure facilities, etc. The system we have devised using ICT and RFID technologies supports not only authentic transactions among all university departments, but also interconnects all levels of academic life and activity. Thus, the utility of the system ranges from access control (student/ staff/ visitor identification), attendance tracking, library check-out services and voting to grade book consulting, inventory, cashless vending, parking, laundry and copying services. Physically, the system consists of several RFID gates/readers, a data server and some network stations, all of them requiring specific structuring and integration solutions. The system is quite different from already existing ones in that it proposes an innovative access solution. Thus, the search of the ID card holder in a database has been replaced by local processing. Since one and the same card is employed to perform a variety of operations, the system has immediate and numerous utilizations.
In this paper is presented the management software proposed for portable readers and desktops for... more In this paper is presented the management software proposed for portable readers and desktops for a livestock 13,56 MHz RFID transponder based system. The program was created according with specific laws for cattle, but can easily be adapted for sheep, hogs, horses or even pets. The management program provides a robust software package with capabilities of importing and exporting data to memory tags. It is designed for the medium to large size farms, for meat producer to assist in management process or even townhalls. The program provides analysis of cow and calf performances in order to optimize production. Both versions, Romanian and English were created.
Over the past few years, special attention has been paid to biomass valorization. The aim of this... more Over the past few years, special attention has been paid to biomass valorization. The aim of this paper is to evaluate the effect of the phenolic rich extracts obtained from raw materials on the growth and development of lemon balm (Melissa officinalis L.). The extracts were obtained from the bark of spruce (Picea abies (L.) H. Karst) and beech (Fagus sylvatica L.) separated as waste product during wood processing. The growth and development of the plants was assessed by measuring elongation of vegetative organs, biomasses including root, stem, and leaf, and photosynthetic pigment content. In addition, the analysis of some histo-anatomic characteristics of the vegetative organs were made. Elongation biomasses and photosynthetic pigments concentration presented higher values in case of plants treated with beech bark phenolic extract compared to control plants. The spruce bark phenolic extract had a stimulatory effect on the germination but inhibited the growth and development of the plants. Both extracts increased the percentage of lignification in stems. These findings could contribute to the development of natural and eco-friendly substances that favor cultivation of lemon balm plants. Future research is needed in order to identify potential qualitative and quantitative changes in the essential oil of the aromatic plant treated with the tested solutions.
This paper presents a modern RFID system for campus access and facilities. The system works in 13... more This paper presents a modern RFID system for campus access and facilities. The system works in 13,56 MHz range, according with ISO 15693 standard. An innovative access method using data blocks instead of searching ID card holder in a database is presented. Besides access control, the system can also provide: cashless vending for student restaurant, parking, laundry, copiers, cafeteria services, library check out services, logical access control to online research and other digital resources, automatic access to students events and activities, transcript of academic record.
2015 9th International Symposium on Advanced Topics in Electrical Engineering (ATEE), 2015
ABSTRACT An important aspect that should be taken into consideration when we talk about RFID syst... more ABSTRACT An important aspect that should be taken into consideration when we talk about RFID systems is the antenna impedance matching. When a mismatch occurs in the antenna circuit, the power transferred from the RFID reader to its antenna is reflected, causing drastically decreasing of the tags reading distance. In this paper are analyzed some matching impedance circuits for an HF RFID reader antenna and are proposed few methods to achieve the desired impedance. The obtained results confirm that when a standard RFID reader antenna is used and the impedance isn't matched, the maximum reading distance decreases up to 60% towards when is well matched.
In this paper, we present the design, development and implementation of an integrated system for ... more In this paper, we present the design, development and implementation of an integrated system for the management of COVID-19 patient, using the LoRaWAN communication infrastructure. Our system offers certain advantages when compared to other similar solutions, allowing remote symptom and health monitoring that can be applied to isolated or quarantined people, without any external interaction with the patient. The IoT wearable device can monitor parameters of health condition like pulse, blood oxygen saturation, and body temperature, as well as the current location. To test the performance of the proposed system, two persons under quarantine were monitored, for a complete 14-day standard quarantine time interval. Based on the data transmitted to the monitoring center, the medical staff decided, after several days of monitoring, when the measured values were outside of the normal parameters, to do an RT-PCR test for one of the two persons, confirming the SARS-CoV2 virus infection. We h...
Energy management efficiency is a topical issue for Internet of Things (IoT) sensor networks beca... more Energy management efficiency is a topical issue for Internet of Things (IoT) sensor networks because a sensor can be placed in harsh or hardly accessible places and must transmit data without maintenance. One characteristic of the LoRa technology is the high current peaks during the data transmission procedure. These current peaks can decrease the lifetime of the conventional power sources. Thus, to protect the conventional battery of the wireless sensor from degradation during fast discharging, a hybrid energy storage system can help. This article presents the design and development of a LoRaWAN sensor powered by a hybrid energy storage system and an energy management solution that can be integrated into the node. The novel solution presented integrates a 330-mW photovoltaic (PV) panel as a main source, a 4-F supercapacitor and a 230-mA small form factor Lithium battery as backup and it was tested in a real IoT application. Currently, as the most used solution to increase the battery lifetime of a LoRaWAN sensor is to reduce the communication time with the Gateway, our hybrid power management system comes with a solution for the node to be powered for a very long period of more than two years in worst case scenario configuration when the PV panel is not installed and more than ten years with hybrid power solution, without the compromise of reducing the communication time. The achieved communication distance is about 580 m with SF7 and more of 2 km with SF12 in an urban area.
This article presents a novel visible light communications receiver architecture, designed for au... more This article presents a novel visible light communications receiver architecture, designed for automotive applications. A central problematic in this area is the design of a suitable receiver able to face the problems caused by the dynamic situations, by the long distances and also by the environmental conditions. In such circumstances, a solution would be to adapt the communication's data rate to channel conditions, meaning that the communication would take place using different data rates depending on the signal to noise ratio (SNR) and the message priority. Considering the digital filtering better performances, the proposed architecture considers the usage of digital signal processing (DSP) as an alternative to the analog signal treatment. The visible light communication receiver proposed in this article addresses the upper mentioned issues and enables a robust communication even at low SNR.
This paper proposes an implementation of access control gates in a distributed administration sys... more This paper proposes an implementation of access control gates in a distributed administration system, based on RFID technologies (RFID tags). Within this administration system, we emphasize the independent stations controlling the access through different gates, as well as the architectures of the involved hardware and software part.
2015 International Symposium on Signals, Circuits and Systems (ISSCS), 2015
This paper presents a low cost and a low profile flexible microstrip patch tag antenna for UHF RF... more This paper presents a low cost and a low profile flexible microstrip patch tag antenna for UHF RFID systems that can be metal mountable. The simple design that doesn't imply using shorting pins, flexibility and small size (25mm × 50mm × 0.5mm) are a few of the advantages given by this design. The proposed antenna is simulated and the results obtained are compared with measurements performed with Agilent FieldFox N9912A VNA. At ETSI frequency band, the reading distance is up to 2.7m, which shows that the tag achieves good size/performance ratio for flexible metal mountable UHF RFID tags. The gain of the antenna is only -16.25dB, but in order to reach the mentioned reading distance is used an RFID chip having a wake-up power of -20.5dBm. The proposed tag can be easily mounted on metallic objects having various sizes and shapes.
Many efforts where made in the last years in order to develop new techniques for mobile objects i... more Many efforts where made in the last years in order to develop new techniques for mobile objects identification, location and tracking. Radio Frequency Identification (RFID) systems are a possible solution to this problem. There are many different practical implementations of such systems, based on the use of radio waves from low frequencies to high frequencies. In this paper we present a short review of existing RFID systems, and an in depth analysis of one commercial system, the RFID RADAR. The results are from experiments performed in real life conditions. Also, this paper offers important EMC information regarding the use of high frequency RFID system.
Reading RFID tags positioned at different angles is an important aspect especially if exists a me... more Reading RFID tags positioned at different angles is an important aspect especially if exists a metallic environments influence over the reader antenna. In this paper is proposed one successfully solution of the problem generated by presence of metallic environments ...
Abstract: In this paper we present an evaluation of location systems available commercially on th... more Abstract: In this paper we present an evaluation of location systems available commercially on the world market as full working systems or as prototype and evaluation versions. We made tests for both location precision and electromagnetic field emissions in order to find out the ...
The digital revolution has changed the way we implement and use connected devices and systems by ... more The digital revolution has changed the way we implement and use connected devices and systems by offering Internet communication capabilities to simple objects around us. The growth of information technologies, together with the concept of the Internet of Things (IoT), exponentially amplified the connectivity capabilities of devices. Up to this moment, the Long Range (LoRa) communication technology has been regarded as the perfect candidate, created to solve the issues of the IoT concept, such as scalability and the possibility of integrating a large number of sensors. The goal of this paper is to present an analysis of the communication collisions that occur through the evaluation of performance level in various scenarios for the LoRa technology. The first part addresses an empirical evaluation and the second part presents the development and validation of a LoRa traffic generator. The findings suggest that even if the packet payload increases, the communication resistance to inter...
The paper summarizes our preliminary findings regarding the development and implementation of a n... more The paper summarizes our preliminary findings regarding the development and implementation of a newly proposed system based on ICT and RFID (Radio Frequency Identification) technologies for campus access and facility usage. It is generally acknowledged that any educational environment is highly dependent upon a wide range of resources or variables such as teaching staff, research and study areas, meeting and accommodation facilities, library services, restaurant and leisure facilities, etc. The system we have devised using ICT and RFID technologies supports not only authentic transactions among all university departments, but also interconnects all levels of academic life and activity. Thus, the utility of the system ranges from access control (student/ staff/ visitor identification), attendance tracking, library check-out services and voting to grade book consulting, inventory, cashless vending, parking, laundry and copying services. Physically, the system consists of several RFID gates/readers, a data server and some network stations, all of them requiring specific structuring and integration solutions. The system is quite different from already existing ones in that it proposes an innovative access solution. Thus, the search of the ID card holder in a database has been replaced by local processing. Since one and the same card is employed to perform a variety of operations, the system has immediate and numerous utilizations.
In this paper is presented the management software proposed for portable readers and desktops for... more In this paper is presented the management software proposed for portable readers and desktops for a livestock 13,56 MHz RFID transponder based system. The program was created according with specific laws for cattle, but can easily be adapted for sheep, hogs, horses or even pets. The management program provides a robust software package with capabilities of importing and exporting data to memory tags. It is designed for the medium to large size farms, for meat producer to assist in management process or even townhalls. The program provides analysis of cow and calf performances in order to optimize production. Both versions, Romanian and English were created.
Over the past few years, special attention has been paid to biomass valorization. The aim of this... more Over the past few years, special attention has been paid to biomass valorization. The aim of this paper is to evaluate the effect of the phenolic rich extracts obtained from raw materials on the growth and development of lemon balm (Melissa officinalis L.). The extracts were obtained from the bark of spruce (Picea abies (L.) H. Karst) and beech (Fagus sylvatica L.) separated as waste product during wood processing. The growth and development of the plants was assessed by measuring elongation of vegetative organs, biomasses including root, stem, and leaf, and photosynthetic pigment content. In addition, the analysis of some histo-anatomic characteristics of the vegetative organs were made. Elongation biomasses and photosynthetic pigments concentration presented higher values in case of plants treated with beech bark phenolic extract compared to control plants. The spruce bark phenolic extract had a stimulatory effect on the germination but inhibited the growth and development of the plants. Both extracts increased the percentage of lignification in stems. These findings could contribute to the development of natural and eco-friendly substances that favor cultivation of lemon balm plants. Future research is needed in order to identify potential qualitative and quantitative changes in the essential oil of the aromatic plant treated with the tested solutions.
This paper presents a modern RFID system for campus access and facilities. The system works in 13... more This paper presents a modern RFID system for campus access and facilities. The system works in 13,56 MHz range, according with ISO 15693 standard. An innovative access method using data blocks instead of searching ID card holder in a database is presented. Besides access control, the system can also provide: cashless vending for student restaurant, parking, laundry, copiers, cafeteria services, library check out services, logical access control to online research and other digital resources, automatic access to students events and activities, transcript of academic record.
2015 9th International Symposium on Advanced Topics in Electrical Engineering (ATEE), 2015
ABSTRACT An important aspect that should be taken into consideration when we talk about RFID syst... more ABSTRACT An important aspect that should be taken into consideration when we talk about RFID systems is the antenna impedance matching. When a mismatch occurs in the antenna circuit, the power transferred from the RFID reader to its antenna is reflected, causing drastically decreasing of the tags reading distance. In this paper are analyzed some matching impedance circuits for an HF RFID reader antenna and are proposed few methods to achieve the desired impedance. The obtained results confirm that when a standard RFID reader antenna is used and the impedance isn't matched, the maximum reading distance decreases up to 60% towards when is well matched.
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Papers by Valentin POPA