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In our everyday life, travellers pay an assured amount of tax all the way through toll plaza to the government. The national highways and bridges have toll gates, where people pay the charges for using the highways by standing in the queue, leading to unnecessary break of journey. Therefore, in order to abstain this issue, this proposed system approach for automating the payments of toll plaza by using a Radio Frequency Identifier (RFID) and security algorithm. In the proposed work, the user is allowed to login with the RFID system and can enter the source and destination. Then, the system shows the possible toll booths that blow in the way. After selecting the toll booths on the user's way, the user is redirected to the payment gateway. The payment gateway is encrypted to promote security. In order to abstain maltreatment of the system, the RFID is merged with the vehicle's number. A sensor is applied in every signal, to dig up the time at which the vehicle has passed by.

The first bilateral lightwave network analyzer (BLNA) architecture that is capable of two-port S-parameter measurements is reported in this paper. A combined two-tier calibration is proposed and implemented for electrooptic and optoelectronic measurements. Calibrated measurement results showing the good performance of the BLNA for all types of lightwave components are also presented.

A 96-element active grid with omnidirectional transmission and reception capabilities is demonstrated in this paper. Experimental results are presented at C-band for radiation patterns, self-mixing characteristics, and injection locking to an external source. Graceful degradation in the omnidirectionality and power are also observed.

A quasi-optical self-oscillating mixer (SOM) consisting of a pair of transistor-loaded grids mounted on opposite sides of a two-dimensional photonic crystal (PC) is presented. The PC facilitates mutual injection locking between the grids and extends the operating range of the SOM by minimizing injection locking to an external source. By combining this with electronic tuning of the free-running oscillation frequency, total elimination of the injection-locking range can be achieved. Radiation patterns at C-band also indicate the ability to detect RF signals in three dimensions.

A perforated ground plane is used to suppress the coupling between adjacent and intersecting transmission lines. Experimental results indicate 40-dB suppression of broadside coupling between two adjacent 50-/spl Omega/ lines. A new option in the design of circuit routing schemes is proposed by demonstrating 28-dB coupling reduction between two intersecting 50-/spl Omega/ lines.

A plastic, 95-GHz rectangular waveguide with an integrated plastic flange has been successfully demonstrated using micro hot embossing and electroplating technologies. The prototype device shows s/sub 11/ and s/sub 21/ values of -20.7 dB and -1.35 dB at 95GHz, respectively, and the signal transmission rate is 73.3% as compared to commercial all-metal waveguides at 85%. The time domain measurement showed the system losses are mainly due to the discontinuity losses at the interfaces between the network analyzer adaptors and the waveguide input/output ports and could be further minimized in future integrated systems. As such, this new class of plastic waveguides has potential applications in replacing the expensive yet bulky/heavy metallic waveguides in current millimeter-wave systems.

The increasing use of microwave fibre-optic links requires that efficient and accurate lightwave network analysers and techniques are developed. This paper follows from previous work done on a bilateral test set for lightwave networks. Theoretical simulations have been carried out which have demonstrated the viability of this approach for lightwave measurements. The advantage of the proposed network is that it can be used as a black box to convert a microwave network analyser into a lightwave network analyser.

The thru-attenuator-x (TAx) family of calibration techniques has been implemented for a two-port optical test set. A wide variety of results demonstrating the good performance of these techniques applied to optical components are presented.

Commercial lightwave analysers use advanced normalisation techniques to implement optical calibration. As integrated optical components gain wider usage, leakage effects cannot be neglected, and hence there will be an increasing need to perform 16-term calibration. One of the main constraints at present to implement optical 16-term or even 12-term calibration is the lack of enough optical reflection standards. Given the bandwidth limitation of the line standard, it is desirable to have at least three optical reflection standards in addition to the thru standard. In this work, a variable optical reflection standard which makes use of bulk optics is proposed. The structure consists of a fibre pigtail, a lens and a mirror all separated by air. The variation in optical reflection is produced by varying the distance between the lens and the other two elements.

A quasi-optical linearizer array with bias controllable AM-AM and AM-PM predistortion characteristics is presented. The 4/spl times/4 array of Schottky diodes demonstrates 2.5 dB of gain expansion and 25/spl deg/ of phase compensation at L band.

Phased arrays with reduced cost and increased power handling capability are important for commercial applications. In this paper, we demonstrate beam-steering arrays using reconfigurable periodic structures in the ground plane without solid-state phase shifters. A linearly discrete beam-steering of 35/spl deg/ in steps of approximately 6/spl deg/ has been achieved at a fixed frequency of 5.6 GHz. The main beam power varied less than 2 dB over the whole range of beam-steering. A frequency-dependent beam-steering of 15/spl deg/ is also achieved from 5 GHz to 6 GHz.

The increasing use of microwave photonic components in applications such as optical generation, distribution and processing of microwave signals, antenna beam forming and optical control of microwave devices has brought a corresponding need for accurate component characterisation. In particular, new tools will be required for the measurement of fundamental quantities such as the microwave frequency response, bandwidth, gain and return loss of microwave photonic components. However, existing approaches to microwave photonic network analysis are primitive when compared with conventional microwave network analysis. This paper will provide a review of the theory and techniques used for microwave photonic component characterisation. State-of-the-art architectures for microwave photonic component network analysers and the corresponding optical calibration techniques that have been developed at The University of Leeds are described. (6 pages)

The widespread use of photonic systems having microwave modulation bandwidths, coupled with the inclusion of photonic components in microwave and millimetre-wave systems, is creating a demand for efficient characterisation techniques. In particular, new tools will be required for the measurement of fundamental quantities such as the microwave frequency response, bandwidth, gain and return loss of microwave photonic components. However, existing lightwave measurement techniques are primitive when compared with conventional RF and microwave network analysis. This paper provides a review of the theory and techniques used for the small-signal characterisation of microwave photonic components. State-of-the-art architectures for lightwave network analysers and the corresponding two-port calibration techniques are described.