Quadrature Phase Shift Keying

Abstract: ABSTRACT QUADRATURE PHASE SHIFT KEYING Quadrature Phase Shift Keying (QPSK) is a form of Phase Shift Keying in which two bits are taken at a time and modulated, selecting one of four possible carrier phase shifts (0, 90, 180, or 270 degrees). QPSK allows the signal to carry twice much information than ordinary PSK, using the same bandwidth. Compared to modulation schemes that transmit one bit per symbol, QPSK is advantageous in terms of bandwidth efficiency. For example, imagine an analog baseband signal in a BPSK (binary phase shift keying) system. BPSK uses two possible phase shifts instead of four, and thus it can transmit only one bit per symbol. The baseband signal has a certain frequency, and during each symbol period, one bit can be transmitted. A QPSK system can use a baseband signal of the same frequency, yet it transmits two bits during each symbol period. Thus, its bandwidth efficiency is (ideally) higher by a factor of two. QPSK is used for satellite transmission of MPEG2 video, cable modems, videoconferencing, cellular phone systems, and other forms of digital communication over an RF carrier.

Patent Information

Application #

Filing Date

15 November 2019

Publication Number

49/2019

Publication Type

INA

Invention Field

COMMUNICATION

Status

Email

Parent Application

Applicants

Dr.MOHAN E

25, PAVALA VANNER STREET, BIG KANCHIPURAM, Tamilnadu, India.

Dr.ASWIN KUMER S V

Associate Professor, Department of Electronles and Communication Engineering, Koneru Lakshmalah Education Foundation, Vaddeswaram, Andhra Pradesh-522502, India.

Inventors

1. Dr.MOHAN E

25, PAVALA VANNER STREET, BIG KANCHIPURAM, Tamilnadu, India.

2. Dr.ASWIN KUMER S V

Associate Professor, Department of Electronles and Communication Engineering, Koneru Lakshmaiah Education Foundation, Vaddeswaram, Andhra Pradesh-522502, India.

3. V.RAMANI KUMAR

Adjunct Professor, Department of Electronics and Communication Engineering, Koneru Lakshmaiah Education Foundation, Vaddeswaram-522502, Andhra Pradesh, India.

4. PAMARTHI KANAKARAJA

Assistant Professor, Department of Electronics and Communication Engineering, Koneru Lakshmaiah Education Foundation. Vaddeswaram-522 502, Andhra Pradesh, India

5. L S P SAIRAM NADIPALLI

Assistant Professor, Department of Electronics and Communication Engineering, Koneru Lakshmaiah Education Foundation. Vaddeswaram-522 502, Andhra Pradesh, India

Specification

CLAIMS
We claim:
1. An Implementation of Quadrature Phase Shift Keying using
JKFlip Flop (4027) and 4:1 Multiplexer (4052) comprising:
a. JKFlip Flop (IC 4027}
b. Quad Op-Amp (LM324)
c. 4:1 Multiplexer (1C4052)~
d. D Flip Flop (!C 4013)
e. Timer (IC 555)
f. Ex-orGate(IC4030)
2. An Implementation of Quadrature Phase Shift Keying using JK Flip
Flop (4027) and 4:1 Multiplexer (4052) as claimed in claim 1,
comprising of a Johnson counter is constructed using JK Flip flop,
which generate the four phases of square waves.
3. An Implementation of Quadrature Phase Shift Keying using JK Flip Flop (4027) and 4:1 Multiplexer (4052) according to claim 1, the clock signal for the Johnson counter is generated using Timer IC (IC555), which is operating in Astable Mode.

4. An Implementation of Quadrature Phase Shift Keying using JK Flip Flop (4027) and 4:1 Multiplexer (4052) according to claim 1, includes Quad Op-amp (LM324), which is having four numbers of operational amplifiers. The four numbers of operational amplifiers are used to design four number of second order Low Pass Filters to convert square waves generated from Johnson counter into Sine waves of four different phases. Those sine waves are going to act as a carrier signal for QPSK.
5. An Implementation of Quadrature Phase Shift Keying using JK Flip Flop (4027) and 4:1 Multiplexer (4052) according to claim 1, the Pseudo Random Bit Sequence (PRBS) Generator is designed using D-Flip Flop (IC4013) and Ex-Or Gate (IC4030), constructed in Linear Feedback Shift Register (LFSR) mode to generate Random DATA bits, used as select inputs for 4:1 Multiplexer. Those DATA bits are going to act as a message signal for QPSK. The one output out of four outputs from Johnson counter acts as a clock signal for the PRBS generator.

6. An Implementation of Quadrature Phase Shift Keying using JK Flip Flop (4027) and 4:1 Multiplexer (4052) according to claim 1, the four sine waves with different phase shifts are applied to the 4:1 multiplexer. Based on the select inputs from PRBS Generator, the IC 4052 selects the sine wave carrier and the QPSK output is obtained from the 4:1 Multiplexer.

Documents

Application Documents

#	Name	Date
1	Form9_Earlier Publication_15-11-2019.pdf	2019-11-15
2	Form2 Title Page_Complete_15-11-2019.pdf	2019-11-15
3	Form18_Normal Request_15-11-2019.pdf	2019-11-15
4	Form 5_As Filed_15-11-2019.pdf	2019-11-15
5	Form 3_As Filed_15-11-2019.pdf	2019-11-15
6	Form 1_As Filed_15-11-2019.pdf	2019-11-15
7	Drawing_As Filed_15-11-2019.pdf	2019-11-15
8	Description Complete_As Filed_15-11-2019.pdf	2019-11-15
9	Correspondence by Applicant_As Filed_15-11-2019.pdf	2019-11-15
10	Claims_As Filed_15-11-2019.pdf	2019-11-15
11	Abstract_As Filed_15-11-2019.pdf	2019-11-15
12	201941046516-FER.pdf	2021-10-17

Search Strategy

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