Security system using biometric technology: Design and implementation of voice recognition system (VRS)

Biometric technology is fast gaining popularity as means of security measures to reduce cases of fraud and theft due to its use of physical characteristics and traits for the identification of individuals. The earliest methods of biometric identification included fingerprint and handwriting while more recent ones include iris/eye scan, face scan, voice print, and hand print. Biometric voice recognition and identification technology focuses on training the system to recognize an individual's unique voice characteristics (i.e., their voice print). The technology lends itself well to a variety of uses and applications, including security access control for cell phones (to eliminate cell phone fraud), ATM manufacturers (to eliminate pin # fraud) and automobile manufacturers (to dramatically reduce theft and carjacking). In this paper, we present an implementation of a security system based on voice identification as the access control key. Verification algorithm is developed using MATLAB (SIMULINK) function blocks which is capable of authenticating a person's identity by his or her voice pattern. A voice match will produce logic '1' while a mismatch, logic '0'. A microcontroller circuit controlling access to a door is built to test the reliability of this voice controlled security system. It is found out that the developed voice recognition software has successfully activated the door opening mechanism using a voice command that ONLY works for the authenticated individual. The system is proven to be able to provide medium-security access control and also has an adjustable security level setting to account for the variations in one's voice each time a voice identification occurs

Experimental study of sensing performance metrics for cognitive radio network using software defined radio platform

Cognitive Radio (CR) is a promising technology in wireless communication for an enhanced utilization of limited spectral resources. It allows unlicensed or cognitive users (CUs) to sense the spectral environment and access a channel exhibiting negligible activity of licensed or primary users (PUs). Hence, spectrum sensing is a crucial task for a CU to perform in an opportunistic spectrum access (OSA) based CR network to avoid harmful interference to PU. Two main performances metrics that are crucial in the design of spectrum sensing are the probability of false alarm ( P fa ) and the probability of detection ( P d ). These metrics are used to define the CR system quality of service (QoS). The threshold to decide on the presence of PU and the sensing time needed for the CR system are also determined based on these metrics. This paper presents the design of measurement methods to experimentally acquire the P fa and P d curves based on locally captured data to determine the value of the threshold and sensing time. The implementation, experimentation and measurement are done using GNU Radio and universal software defined radio peripheral (USRP) software defined radio (SDR) platform as the cognitive radio testbed. Spectrum sensing was done based on energy detection. Each of the energy based detection measurement is repeated 1000 times to obtain an accurate estimation of P fa and P d . The findings show that the target Quality of Sevice (QoS) of P fa of 5% and P d of 90% can be derived from the estimated sensing threshold of -39 dB and achieves a sensing time of 31.59 ms

2.4GHZ ISM band congestion : WLAN and WPAN performance analysis

The 2.40 GHz frequency band is also known as the ISM (Industrial Scientific and Medical) band, is a license free band allocated for a variety of consumer applications: environmental monitoring, agriculture, medical care, smart buildings, factory monitoring and automation, and numerous military applications. A wireless sensor network (WSN) consist of small nodes with sensing, computation, and wireless communications capabilities, is an exciting new technology and can also be considered as the underlying infrastructure that will be an integral part of future ubiquitous and embedded computing applications. Due to the independent design and development in WSN, together with the unexpected dynamics during deployment of co-eXisting networks and devices, within the same frequency spectrum, IT is crucial to ensure that each wireless technology maintains and provide its desired performance requirements. This paper proposes to study multifrequency functionality among overlapping but cooperative WSNs and potential interferences with Wireless Local Area Network (WLAN) are examined according to the impact on the throughput performance of WLAN and WPAN devices when coexisting within a certain environment

Cognitive radio simplex link management for dynamic spectrum access using GNU radio

The explosion of new wireless communication technologies and services has led to the increase in spectrum demand. The fixed spectrum allocation approach has resulted in current day spectrum scarcity and poorly utilized licensed spectrum. In order to overcome these problems, a new concept of accessing the spectrum, defined as dynamic spectrum access (DSA), is proposed. DSA mechanism enables unlicensed or cognitive users (CUs) to temporarily utilize a spectrum hole for a period of time. In this work, DSA based on cognitive radio (CR) technology is chosen due to its features of able to sense, learn, adapt and react according to the environment. The proposed design of the system consists of four main functional blocks: spectrum sensing, spectrum management, spectrum decision and data transmission. Spectrum management is further divided into three parts: spectrum identification, synchronization and link management. This paper focuses on the establishment of link management module in simplex mode. The implementation is done using GNU Radio and USRP SDR platform. The GMSK based and IEEE 802.15.4 standard radios, equipped with DSA capability using CR technique, have been developed and tested. The results show that the link module has successfully maintained CU’s seamless communication while the DSA mechanism offers significant improvement in terms of achieved packet rate ratio (PRR)

Dynamic spectrum access using cognitive radio utilizing GNU radio and USRP

The thirst for spectrum usage is very demanding specifically due to the explosion of new wireless technologies and services. The current static spectrum allocation policy cannot support the need of this demand and it needs to be revised to allow spectrum to be accessed dynamically. Spectrum utilization can be significantly improved by adopting the concept of Dynamic Spectrum Access (DSA) where unlicensed or cognitive users (CUs) can temporarily utilize a spectrum hole for a period of time and move to another spectrum hole whenever the licensed user appears. In this work, cognitive radio (CR) technology is chosen to provide DSA due to its features of able to sense, learn, adapt and react according to the environment. The proposed design of the CR system for DSA consists of four main functional blocks: spectrum sensing, spectrum management, spectrum decision and data transmission. The implementation is done using GNU Radio and USRP SDR platform. The GMSK based radio equipped with DSA capability using CR technique has been developed and implemented. The results show a significant improvement in term of Packet Reception Rate (PRR) in CR with DSA systems

Experimental study of sensing performance metrics for cognitive radio network using software defined radio platform

Cognitive Radio (CR) is a promising technology in wireless communication for an enhanced utilization of limited spectral resources. It allows unlicensed or cognitive users (CUs) to sense the spectral environment and access a channel exhibiting negligible activity of licensed or primary users (PUs). Hence, spectrum sensing is a crucial task for a CU to perform in an opportunistic spectrum access (OSA) based CR network to avoid harmful interference to PU. Two main performances metrics that are crucial in the design of spectrum sensing are the probability of false alarm (P-fa) and the probability of detection (P-d). These metrics are used to define the CR system quality of service (QoS). The threshold to decide on the presence of PU and the sensing time needed for the CR system are also determined based on these metrics. This paper presents the design of measurement methods to experimentally acquire the P-fa and P-d curves based on locally captured data to determine the value of the threshold and sensing time. The implementation, experimentation and measurement are done using GNU Radio and universal software defined radio peripheral (USRP) software defined radio (SDR) platform as the cognitive radio testbed. Spectrum sensing was done based on energy detection. Each of the energy based detection measurement is repeated 1000 times to obtain an accurate estimation of P-fa and P-d. The findings show that the target Quality of Sevice (QoS) of P-fa, of 5% and P-d of 90% can be derived from the estimated sensing threshold of -39 dB and achieves a sensing time of 31.59 ms

The status of seabirds at Latham Island, Tanzania

Latham Island, Tanzania, was surveyed in August 2004 — the first known survey of the island outside the period October–March — and in December 2005. On both surveys, four species of seabird were breeding at the island. Larger numbers of swift tern Sterna bergii thalassina and common noddy Anous stolidus plumbeigularis were breeding in August than in December, but the converse was true for masked booby Sula dactylatra melanops and sooty tern Sterna fuscata nubilosa. The estimated breeding populations of the four species were: masked booby (3 700 pairs), swift tern (320 pairs), sooty tern (4 400 pairs) and common noddy (4 000 pairs). These represent about 20%, 50%

Spectrum sensing measurement using GNU radio & USRP software radio platform

Spectrum utilization can be significantly improved by adopting cognitive radio (CR) technology. Such radios are able to sense the spectral environment and use this information to opportunistically provide wireless links that meet the user communications re quirements optimally. To achieve the goal of cognitive radio, it is a fundamental requirement that the cognitive user (CU) performs spectrum sensing to detect the presence of the primary user (PU) signal before a spectrum is accessed as to avoid harmful in terference. Therefore, two probabilities are of interest; the probability of detection, P d and the probability of false alarm, P fa . In this paper, we investigate sensing performance implemented on real -time testbed of GNU Radio and USRP Software Defined Radio (SDR) communi cation platform operating at 2.48 GHz with a bandwidth of 4 MHz. Energy detector utilizing 1024 FFT bin is the sensing mechanism used in the experimental set -up. The acquired experimental results of P d and P fa are duly analyzed and verifie d to be comparable to the curve of the theoretical framework for line -of-sight indoor environment. It is observed that at a target P fa of 5%, the optimal decision threshold for PU detection is -39 dB. The plot of measured number of samples needed for a des ired P d for various received signal levels, representing various signal -to-noise (SNR) conditions, is also included. At SNR of 0 dB and a target Quality of Service (QoS) set at P d of 90%, it is found out that the required sensing time for our GNU Radio USR P based CR system is equal to 31.59ms

The food of three seabirds at Latham Island, Tanzania, with observations on foraging by masked boobies Sula dactylatra

At Latham Island, Tanzania, in August 2004 and December 2005, flying fish (Exocoetidae) contributed 90% by mass of prey items regurgitated by masked boobies Sula dactylatra. The fish had a mean caudal length of 164mm. Two boobies generally foraged in deep water, away from the Tanzanian coastline, ranging up to 390km from the island. Maximum distances flown on trips exceeded 1 000km during breeding and approached 3 000km when not breeding. Some foraging trips exceeded six days. Swift terns Sterna bergii consumed small fish and mantis shrimps Natosquilla investigatoris. Mantis shrimps recovered from the colony were significantly larger than those stranded on the island's beach, suggesting that swift terns preferentially took larger animals. Sooty terns Sterna fuscata fed on small fish and squid.Keywords: food, foraging, Latham Island, masked booby, sooty tern, Sterna bergii, Sterna fuscata, Sula dactylatra, swift ternAfrican Journal of Marine Science 2006, 28(1): 109–11