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Sagar Patel ¹, Devangkumar Patil ²

Affiliations
1 Dept. of E&C Engineering at C S Patel Institute of Technology, Changa, CHARUSAT, IN
2 Dept. of E&C Engineering at Hasmukh Goswami College of Engineering, Ahmedabad, GTU, IN

Abstract

Now a days in wireless data communication field subscriber needs high data rate, lower Bit Error Rate (BER) and also high power efficiency. In Multiple Input Multiple Output (MIMO) the Orthogonal Frequency Division Multiplexing (OFDM) is the best solution to full fill these all requirements. MIMO OFDM is multicarrier modulation technique. The MIMO OFDM is known for its high data rate transmission. In MIMO OFDM the Peak to Average Power Ratio (PAPR) is high which results in power in-efficiency. Low PAPR is required in the uplink because the efficiency of power amplifier is critical due to the limited battery power in a mobile phone.  In this paper we study about all PAPR reduction technique. The advantage of these techniques is efficient PAPR reduction.

Keywords

MIMO:Multiple Input Multiple Output, OFDM:Orthogonal Frequency Division Multiplexing, PAPR:Peak to Average Power Ratio, SQNR:Signal to Quantization Noise Ratio, ADC:Analog to Digital Converter, DAC:Digital to Analog Converter.

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Sagar Patel ¹, Devangkumar Patil ², Dhvanit Mehta ³

Affiliations
1 Dept. of E&C Engineering at C S Patel Institute of Technology, Changa, CHARUSAT, IN
2 Dept. of E&C Engineering at Hasmukh Goswami College of Engineering, Ahmedabad, GTU, IN
3 E&C Department, at C S Patel Institute of Technology, CHARUSAT, Changa, IN

Abstract

In this paper, the performance of Complex orthogonal space-time block codes (COSTBCs) [1] [2] [3] with transmit antenna selection (TAS) with reduced feedback bit in a Rayleigh fading channel is analyzed. Out of the total of Lt transmit antennas, scheme-I, select best 8 transmit antenna, scheme-II, select best four group of each group consist of two transmit antenna, scheme-III, select best two transmit antenna and rest of the six antenna select randomly. Scheme-I gives best compare to Scheme-II, Scheme-III. But within this all schemes, Scheme-III requires less feedback bit compare to other schemes. All three Schemes of TAS have been presented in the article.

Keywords

High Complex Orthogonal Space-Time Block Codes (COSTBCs), Transmit Antenna Selection (TAS) Feedback Bit.

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Sagar Patel ¹, Pravin Thakor ², Jaimin Rami ², Rahul Sathvara ²

Affiliations
1 Dept. of E&C Engineering at C S Patel Institute of Technology, Changa, CHARUSAT, IN
2 Dept. of E&C Engineering at Government Engineering College, Gandhinagar, GTU, IN

Abstract

In the present and future situation in wireless communication the demand is increasing of good and high quality of communication. This is possible to the use of Multi-User MIMO systems. The Multi-User MIMO system downlink channels referred to as Broadcast Channel (BC) and uplink channels referred to as Multiple Access Channel (MAC). In MU-MIMO systems are caused interference and it is cancelled out by using transmission methods for broadcast channel. There are four transmission methods: Block Diagonalization, Tomlinson-Harashima Precoding, Channel Inversion, and Dirty Paper Coding for cancelled interference. In channel inversion method, Interference due to other Signals and inter-antenna interference become cancelled out and minimize noise enhacement. In the Block Diagonalization (BD) method, only the interference from other user signals is cancelled in the process of precoding. Dirty Paper Coding (DPC) is used to cancelled Gaussian noise and interference that is known to the transmitter. Tomlinson-Harashima Precoding (THP) in Decision Feedback Equalization is to cancel the post-cursor ISI error in the transmitter side, and in the DFE past transmit symbols are known without of errors.

Keywords

Multi-User MIMO, Multiple Access Channel (MAC), Block Diagonalization (BD), Dirty Paper Coding (DPC), Tomlinson-Harashima Precoding (THP).

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Pankaj Savani ¹, Sudhanshu Chauhan ¹, Vineet Jain ², Hasumati Raj ¹, Sagar Patel ¹

Affiliations
1 Department of Quality Assurance, Shree Dhanvantary Pharmacy College, Kim, Dist: Surat, Gujarat 394110, IN
2 Department of Pharmacognosy, Shree Dhanvantary Pharmacy College, Kim, Dist: Surat, Gujarat 394110, IN

Abstract

A simple, accurate and precise spectroscopic method was developed for simultaneous estimation of Clopidogrel Bisulphate and Irbesartan in synthetic mixture using simultaneous equation Method. In this spectroscopic method, for Clopidogrel Bisulphate 220.00 nm and 250.00 nm wavelengths were selected for measurement of absorptivity. Both the drugs show linearity in a concentration range of 10-50 μg/ml at their respective λmax with correlation coefficient (r2) of 0.9996 and 0.9998 for Clopidogrel Bisulphate and Irbesartan, respectively. Accuracy, precision and recovery studies were done by QC samples covering lower, medium and high concentrations of the linearity range. The relative standard deviation for accuracy, precision studies were found to be within the acceptance range (< 2%). The limit of determination was 0.243 μg/ml and 0.323 μg/ml for Clopidogrel Bisulphate and Irbesartan, respectively. The limit of quantification was 0.737 μg/ml and 0.980 μg/ml for Clopidogrel Bisulphate and Irbesartan, respectively. Recovery of Clopidogrel Bisulphate and Irbesartan were found to be 99.57 % and 99.68 % respectively confirming the accuracy of the proposed method. % Assay was found to be 99.41 % and 99.22 % for Clopidogrel Bisulphate and Irbesartan, respectively. The proposed method is recommended for routine analysis since they are rapid, simple, accurate and also sensitive and specific by no heating and no organic solvent extraction.

Keywords

Clopidogrel Bisulphate, Irbesartan, Simultaneous Estimation, Validation Method.

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Sudhanshu I. Chauhan ¹, Pankaj D. Savani ¹, Hasumati Raj ¹, Sagar Patel ¹

Affiliations
1 Department of Quality Assurance, Shree Dhanvantary Pharmacy College, Kim, Surat, Gujarat, IN

Abstract

Candesartan Cilexetil is classified as an AT1 Angiotensin II receptor antagonist as a Antihypertensive agent. There are widely used in treatment of diseases like hypertension, heart failure, myocardial infarction and diabetic nephropathy. The clinical and pharmaceutical analysis of this drug requires effective analytical procedures for quality control and Pharmcodynamic and pharmacokinetic studies as well as stability study. There are many article examines published analytical methods reported so far in the literature for the determination of Candesartan Cilexetil in biological samples and pharmaceutical formulations. These article comprise reviews of analytical methods like Spectrophotometric methods, Chromatographic method including HPLC, HPTLC.

Keywords

Candesartan Cilexetil, Spectrophotometry, HPLC, Anti-Hypertensive Agent, AT1 Angiotensin II Receptor Antagonist.

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Pankaj Savani ¹, Vineet Jain ², Hasumati Raj ¹, Sagar Patel ¹

Affiliations
1 Department of Quality Assurance, Shree Dhanvantary Pharmacy College, Kim, Dist: Surat, Gujarat-394110, IN
2 Department of Pharmacognosy, Shree Dhanvantary Pharmacy College, Kim, Dist: Surat, Gujarat-394110, IN

Abstract

Clopidogrel Bisulphate is a mainly use in Anti platelet agent as a ADP receptor blocker and administration of oral tablet dosage form. Chemically, it is Methyl 2-(2- Chlorophenyl) -2-(6, 7-dihydro thieno [3,2-C] Pyridine- 5(4H)-yl) Acetate sulphate. It is used in the treatment of various cardiovascular diseases like Ischemic stroke as well as in Glomerular inflammation, Myocardial infarction, Atherosclerosis disease, Unstable Angina. An extensive survey of the literature published in various analytical and pharmaceutical chemistry related journals has been conducted and the instrumental analytical methods which were developed and used for determination as single or combination with other drugs in bulk drugs, formulations and biological fluids have been reviewed. These reviews of analytical methods including Spectrophotometric methods like Spectrophotometry, Chromatographic method including HPLC, HPTLC were reported.

Keywords

Clopidogrel Bisulphate, Analytical Methods, Compendial Method, UV Spectroscopic Method, Chromatographic Methods.

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