Abstract: Wireless sensor nodes consume lots of energy during communication but huge power consumption has been observed during active listening in idle mode as source nodes can start data transmission at any time. Power saving can be achieved by establishing synchronization among end nodes. Many rendezvous solutions are available and out of which wake up receiver found extremely adroit. A non volatile wake up transceiver has been proposed in the present paper that works on the basis of ID matching. State of art using 4GB of memory to remember states of sensor nodes while proposed technique used only 60 bits of memory with very less false alarm probability. Power consumption for proposed model is only 59.47 nW. Hence this model is quite effective in terms of power consumption and memory usage as compared to trailing models.
The flexibility of an UWB SDR transceiver implementa- tion must be gained by a huge computational effort neces- sary for the wideband digital signal processing of a band- width in excess of 500 MHz as required by the regulation. In ordinary SDR designs the signal on an intermediate fre- quency (IF) is digitized whereas up- and downconversion to the radio frequency (RF) band afford additional analog mixer stages (see Fig. 1 top) causing signal distortions due to their non-ideal transfer characteristic. Employing bandpass sam- pling (Vaughan et al., 1991) a subsampling direct conversion transceiver can be implemented avoiding any analog circuitry except for bandpass filters and optional amplifiers (see Fig. 1 bottom). First order sampling on the one hand relaxes the requirements of the DAC stage, but on the other hand limits the usable frequency range (Vaughan et al., 1991). Second order sampling offers more advantages in terms of frequency agility, but in turn requires more complex digital signal pro- cessing (Coulson et al., 1994). The application of either of these concepts is difficult in narrowband communications because of noise aliasing, but in UWB systems the perfor- mance degradation due to noise folding is negligible (Chen and Brodersen, 2007).
C R is envisioned as the most promising wireless technology for optimizing the usage of radio frequency spectrum and for insuring reliable communication . Even though OFDM based systems have been proposed to be the most promising candidate for CR transmission -, recent research work propose wavelet based schemes to be an alternative modulation technique in terms of flexibility, adaptivity, and spectrum efficiency -. The efficacy of scalar wavelet packets for CR based systems has been explored and various results are discussed in  - . Both analytical and experimental results show that scalar wavelet based schemes insures better flexibility, sidelobe suppression and reconfigurability at moderate complexity but the research has been limited to single user environment. As WPM is a generalization of Time Division Multiplexing (TDM) and Frequency Division Multiplexing (FDM) it can be considered in a multiuser network with necessary modifications. Hence a Wavelet Packet based Multi Carrier Multiple Access scheme (WP-MC-MA) for CR applications is first proposed in . In this paper the detailed uplink and downlink system models and signal representations are explained. The performance of the system is evaluated using standard orthogonal wavelet basis functions and is compared with OFDMA. The bit error rate under multi-path fading is simulated which is crucial in wideband wireless links. Effect of phase and frequency offset in both uplink and downlink channels are evaluated. The spectrum efficiency and computational complexity of the proposed system are analyzed.
Abstract. In this paper, we propose a new technique to ex- tract low power UWB pulse radio signals, near to noise level, using statistical correlation technique in frequency domain. The receiver consists of many narrow bandpass filters which extract energy either from transmitted UWB signal, interfer- ing channels or noise. Transmitted UWB data can be elim- inated by statistical correlation of multiple bandpass filter outputs. Super-regenerative oscillators, tuned within UWB spectrum, are designed as bandpass filters. Summers and comparators perform statistical correlation.
Sensor nodes ( Field devices) : Each sensor network node has typically several parts, a radiotransceiver with an internal antenna or connection to an external antenna, a micro controller, an electronic circuit for a) Interfacing with the sensors and an energy source usually a battery or an embedded form of energy harvesting. b) Gateway or Access points – A gateway enables communication between host application and field devices. c) Network manager – A network manager is responsible for configuration of the network, scheduling communication between devices, management of the routing tables and monitoring and reporting the health of the network. d) Security manager – The security manager is responsible for the generation, storage and management of keys.
Sensor node are designed to collect raw signals from human body. A sensor node undertakes three tasks: detecting signal via a front-end, digitizing/coding/controlling for a multi access communication and finally wireless transmission via a radiotransceiver technology. The signal from a human body is usually weak and coupled with noise. Thus, the signal should go through an amplification process to increase the signal strength. It then passes through a filtering stage to remove unwanted signals and noise. After which, it will go through an analog to digital conversion (ADC) stage to be converted into digital for digital processing. The digitized signal is then processed and stored in the microcontroller. It will then pack those data and transmit over the air via a transmitter.
A number of state-of-the-art cognitive radiotransceiver design algorithms have been proposed in the literature, which also aim to eliminate the co-channel interference to the primary receivers, and to improve the utilization of the licensed spectrum. The authors in  used the maximum eigenmode beamforming algorithm for the transmission between the transmitter and receivers, in which the primary receiver releases some of its eigenmodes for the secondary transmitters. The proposed algorithm allows the opportunistic transmitters to send data for the secondary receivers and to use the same frequency band of a preexisting primary network to guarantee that none of the interference is imposed on the performance of the primary network. The scheme is proposed in  for a single secondary link and then extended to multiple secondary links in  under the assumption of the perfect CSI at all nodes. However, the methods in [9, 10] employ independent optimization. In , authors proposed a fast algorithm to perform interference alignment (IA) in a cognitive radio network. In this work, the interferences at the primary receivers are aligned away from the desired subspaces of the primary receivers. Author in  proposed a selective interference alignment with user selection. The proposed algorithm judiciously chooses a set of cognitive transmitters to be aligned to each primary receiver as a subset of the cross-tier interferers. The selective algorithm considers a
The applications of RFID became more popular and playing key role in these modern days, including public transportations, open air events, supplying management, airports, access control to buildings. This preferred RFID has to meet some special features like low cost, long operation range, high rate and it has to develop on small area and low power consumption. Passive RFID tags are better than active RFID tags because of the main reason behind it are low cost and maintenance free. In passive RFID tags, power supply has taken from the incident RF EM wave transmitted by readers. The power consumption for this particular type RFID constrains extremely low. In present days, we need to achieve the specialization of ultra low power consumption system; different wireless standards like Wi-Fi and Bluetooth will not achieve this criterion. Ultra Wideband Technique with impulse radio has the possibility to achieve not only the criterion but also the long range, position location, low cost, high throughput and etc. This is integrated in RFID. That’s the reason why this RFID is trending now. This Ultra Wideband (UWB) technique offers short duration impulses; by this it overcomes the possibility of jamming. So, this makes free and good for communication. Here we don’t need any cryptographic techniques. From this we can understood that it takes less chip area and power consumption too. Also it proposes with the low cost it covers wide range. Performance of multiple access has done at great extend in this UWB communication. By this, we don’t need any anti-collision complex circuits. It can able to achieve more tags within less period of time and also has special advantages of locating and ranging, which can additionally add to the system. This has become the powerful and key factor for positioning and monitoring applications.
From last decades the work on various aspects of Bluetooth and its performances is very less as compared to shipments available in Bluetooth. Bluetooth performance should be focused on Packet Error Rate (PER), Throughput, Bit Error Rate (BER), latency, packet delay, discovery time, battery lifetime, security, and goodput in the presence of the heterogeneous wireless environment. Since the Internet of Things (IoT) needs devices with a high data rate, fast connectivity, and more battery life time. Bluetooth can give better performance in this scenario and will be a better option for such applications. The emergence of Bluetooth 5 with the high data rate, range performance, increases the Bluetooth utility in various wireless applications. However, these performances should be maintained in heterogeneous wireless environments, . From the available literature, performance of Bluetooth is affected in the presence of Radio Access Devices (RADs) operating in the same frequency spectrum. To mitigate the interference caused due to nearby radio devices working in the same 2.4GHz Industrial Scientific Medical (ISM) band various techniques were developed in Bluetooth. These techniques were based on collaborative and non-collaborative strategies. In collaborative techniques other Radio Access Technologies (RATs) such as Wireless Local Area Network (WLAN / Wi-Fi), ZigBee, and other Bluetooth networks make spectrum available to either network, . This method is an advantageous due to no change in infrastructure is required, but it hampers the performance and spectral utility of RATs. Other non-collaborative techniques demands modification in physical infrastructure such as the MAC layer and the Physical ————————————————
Radiofrequency waves include electromagnetic waves that have frequencies from 3 kHz to 300 GHz. These waves are often used for telecommunications, radars, satellites, etc. . The use of mobile phones involves frequencies from multiple hundred MHz to several GHz. Since 1980, the Global System for Mobile (GSM) communications has rapidly grown, and the increased demand in global markets has made GSM900/1800 the most popular antennas [2, 3], being widely used throughout the country despite the advent of newer technologies. Since the rise in utilization rates of cellular mobile phones, human health concerns have also increased with regard to the exposure of residents in the vicinity of base transceiver stations (BTS) and related towers to radiofrequency waves and microwaves. Most of the antennas are mounted on masts and at the top of buildings in residential areas; therefore, people might become exposed to radiation. [4-5]. If body organs experience prolonged exposure to microwaves, they are affected by the absorbed energy. If the body fails to compensate for the effects and is unable to return to the normal situation, many organs can get damaged . Adverse effects of microwaves are classified into thermal and non-thermal classes. Thermal effects are caused by the wave-induced temperature rise. Cataract, skin burn, and taste-sense damages are some of the adverse thermal effects of microwaves. In addition, various studies have considered non-thermal effects of microwaves, namely reproductive cells, cancers, mental effects and oxidative changes as well as changes in the stimulation pattern of nerve cells while many other undiscovered aspects remain [7-8].
Cite this article as : Aremu, O. A., Makinde, O. S., Oyinkanola L. O. A., Akande Ademola, "Analytical Study of Radio Frequency Radiation Exposure Level from Different Mobile Base Transceiver Stations in Urban area", International Journal of Scientific Research in Computer Science, Engineering and Information Technology (IJSRCSEIT), ISSN : 2456-3307, Volume 5 Issue 2, pp. 457- 461, March-April 2019. Available at doi : https://doi.org/10.32628/CSEIT195282
Today the wireless communication systems are statically specified by their built in link and physical layer functions. Up until now, the dedicated DSPs have been well known technology associated with the development of SDR systems. However the implementation complexity and cost increases when the digitization of the signal is as close as possible to the antenna. With the recent growth in demand for cellular services and the proliferation of micro and pico-cells, there is an urge to reduce the cost of the base stations. For this reason there is an increasing interest in the SDR systems. The main idea behind SDR systems is that to employ a wideband ADC and all subsequent processing is implemented digitally. By deploying SDR systems we can reduce substantially the cost of the base stations, since a single transceiver is required instead of a transceiver for each channel. Moreover, the flexibility of the base stations is increased in the sense that it can be programmed for different existing standards and for future standards [13, 14].
NEVER connect the transceiver to a power source that is DC fused at more than 5 A. Accidental reverse connection will be protected by this fuse, higher fuse values will not give any protection against such accidents and the transceiver will be ruined.
Baseband processor employs GSM protocol stack for enabling Smartphone to access different types of wireless network technologies such as WCDMA, EDGE, CDMA, Zigbee, Bluetooth 4.0, Wi-Fi, or LTE. BP manages radio communications and control functions such as signal modulation, radio frequency shifting and encoding. Baseband processors were used earlier in ordinary mobile phone technology for accessing cellular network; however, its architecture has evolved in several stages from analog to digital to 3G, and the latest development to LTE. Smartphone has a GSM modem which interfaces with the GSM network.
During transmissions, your Icom radio generates RF energy that can possibly cause interference with other devices or systems. To avoid such interference, turn off the radio in areas where signs are posted to do so. DO NOT operate the transmitter in areas that are sensitive to electromagnetic radiation such as hospitals and blasting sites.
In this paper the working model of Li-Fi is successfully completed. The Li-Fi transceiver using Arduino is designed that is able to transmit digital data. The PCB layout and schematics are sketched using Eagle CAD (version 7.1.0) tool and Proteus design tool (version 8). The software used is MATLAB, Java (ver- sion 8), and serial port monitor. The results show the transmission of data string on the serial port monitor. After ensuring the successful transmission of data string, video frames were transmitted and received successfully. This video trans- mission was seen on JAVA interface. Therefore a Li-Fi prototype has been de- signed which demonstrates the basic principle and also supports the claim of the advantages of Li-Fi over Wi-Fi. The research work presented in this work has some limitations also. The Li-Fi prototype designed does not support multi user access. The speed achieved with this prototype is 115,200 bps only. It is not of high order of Gbps. Also this prototype is not bidirectional. Hence it is only used for broadcast purposes. The limitations of this work can be removed by using higher end devices.
physical properties of LoRa, its gateways can demodulate on multiple channels and multiple signals on the same channel simultaneously. The gateways use different radio frequency components than the end-point to allow high capacity and clearly to enable the gateways to serve like a transparent bridge transferring messages among end- devices and a central network server in the backend. All end-point communication is commonly bidirectional. In addition, it provides operation such as multicast enabling, software upgrade, over the air or other mass delivery messages to decrease the on-air communication time. Different gateways relying on the installation location and the preferred capacity
This paper focuses on robust transceiver design for throughput enhancement on the interference channel (IC), under imperfect channel state information (CSI). In this paper, two algorithms are proposed to improve the throughput of the multi-input multi-output (MIMO) IC. Each transmitter and receiver has, respectively, M and N antennas and IC operates in a time division duplex mode. In the first proposed algorithm, each transceiver adjusts its filter to maximize the expected value of signal-to-interference-plus-noise ratio (SINR). On the other hand, the second algorithm tries to minimize the variances of the SINRs to hedge against the variability due to CSI error. Taylor expansion is exploited to approximate the effect of CSI imperfection on mean and variance. The proposed robust algorithms utilize the reciprocity of wireless networks to optimize the estimated statistical properties in two different working modes. Monte Carlo simulations are employed to investigate sum rate performance of the proposed algorithms and the advantage of incorporating variation minimization into the transceiver design.