Phase Shift Keying Analysis

MODULATION TECHNIQUES
1.4.1 FREQUENCY SHIFT KEYING (FSK)
Frequency shift keying is a frequency modulation in which the digital information is transmitted by discrete changes in frequency of the carrier signal. This technology is used for the communication system such as caller ID and emergency broadcasts [19]. The binary FSK is the simplest FSK. BFSK uses a pair of discrete frequencies to transmit binary information. The 1 and 0 is mentioned as mark frequency and space frequency. The other forms of FSK are Continuous-phase frequency-shift keying, Gaussian frequency-shift keying, Minimum-shift keying, Gaussian minimum shift keying and Audio FSK.
1.4.2 PHASE SHIFT KEYING (PSK)
The Phase Shift Keying is a digital modulation scheme that
To make the SDR platform reconfigurable and flexible, a software-hardware co-implementation approach is adopted in this design where hardware modules can be run- time configured by software drivers. Such feature can be used to maintain quality of service by constantly monitoring channel conditions and changing the operating parameters of the physical layer to compensate for any channel degradation. A central part of the system architecture is a Personal Computer processor. Software code developed in LabVIEW runs on this processor while time critical digital signal processing algorithms are executed by the hardware used namely Universal Software Radio Peripheral (USRP), XBeePro and the WizFi210. By using this generic platform, any protocol can be used for transmitting and receiving the real-time data. One can select any of the digital modulation techniques i.e. FSK, PSK, QAM (4 to 256 bits), and the data is sent in secured form by the use of forward error coding technique namely the convolution coding technique and turbo coding techniques. The designed module has been tested using the NIUSRP hardware and the test jigs for Zigbee and WiFi module by transmitting and receiving data, text and image in real time. With the help of these hardware’s it has been proved that the signal transmitted has been recovered
Power and cost are the most important factors that limit deployment of SDR to both in public and government communication systems.
Some of the major challenges faced by the SDR in the wireless communication industry are as follows:
1. Computational complexity requirements: High processing power is needed to implement different protocols in SDR.
2. Unanimity: Another challenge faced by the SDR is its capability to work with several protocols and frequencies concurrently on the generic platform at the same time.
3. Cost: The cost of an SDR must be less than or equal to that of the cost vital for the development of a conventional hardware for SDR to be widely deployed in telematics.
Ideally, we want to design and implement a generic system where the processing can keep up with the received signal which is being continuously acquired. The rate of processing the signal depends on the efficiency of the implementation, a total number of parallel running applications, the speed at which the host computer works, available memory, and different other factors. Many development platforms are now available for the development of SDR such as NI USRP, Arduino test jigs, GNU radio, etc. that enable dynamic approach in the development of SDR