Motion of the foetal heart gives rise to vibrations and sounds that can be acquired through the surface of the maternal abdominal wall. The process is called foetal phonocardiography (fPCG) and its study has shown to be a very useful mechanism to evaluate the wellbeing of the unborn. These signals exhibit innate rhythms and periodicity that are more readily expressed and appreciated in terms of frequency than time units. Time-frequency distribution shows the spectral composition of signal at a particular time instant, which is also known as a spectrogram. This work investigates the analysis of foetal heart sound using time frequency distribution generated by short-time Fourier transform (STFT). An innovative method is presented for foetal heart sound acquisition, processing and coloured spectral representation, which can be used in a portable foetal home monitoring system. The outcome of the work is a numerous spectral display produced by the system for varied real and simulated foetal heart sound signals. A comparative study of normal and abnormal heart sound is presented. The spectrograms exhibit noticeable morphological differences in terms of duration and spectral composition of the sounds. The study suggests that STFT based coloured spectrograms can become an important diagnostic tool, and it is expected that the presented work will facilitate the potential use of the method in prediction of the prenatal anomalies.

Variations in fetal heart rate (FHR) is a potential indicator of stress on unborn in the womb of mother. In hospitals, FHR surveillance is performed by ultrasound based Doppler equipments. However, recent studies show that frequent exposure to ultrasound radiations is not recommended for the fetal well-being. Because of this and many other reasons, these instruments are not recommended for prolonged home monitoring applications. This work is focused around development of a prototype system for fetal home monitoring application. Presented system can record the abnormal FHR and alert the pregnant women to report to a physician. Recorded data is then processed by a novel methodology for deriving results of diagnostic importance. The instrument has been tested on pregnant women in the clinical environment and has gone through an extensive clinical trial at local hospitals. The results show that the technique is suitable and effective for long-term FHR home monitoring application.

Most of the adhoc routing protocol research work has been done using simulation only because of the difficulty of creating real implementation. In simulation the developer controls the whole system, which is in effect only a single component. An Implementation, on the other hand, needs to interoperate with a large complex system and the system components. In this paper we focus on working implementation of AODV routing protocol by means of certain design possibilities and possible opportunities for obtaining needed AODV events. We discuss the socket based mechanism particularly when AODV routing daemon communicates changes to the IP route table. The paper suggests the need of implementation of Generic Netlink Family.

The register-exchange method (REM) and the trace-back method (TBM) are the two well known methods for survivor path storage and decoding. The REM is logically simple, but it requires large power consumption and large chip area. The TBM is the preferred method used in Viterbi decoders (VD) having large constraint length and high performance. However, the TBM has drawbacks, which requires last-in-first-out (LIFO) buffer and has to use multiple read operations for high speed operation. This multiple operation results in complex control logic. In this paper, we propose a new two approaches or decoding methods called modified trace back method (MTBM) and hybrid register exchange method (HREM). The simulation model is ready and VLSI module is under process. The main advantage of the proposed method is that it reduces the number of decoding operation; memory read operations, less switching activity and fewer requirements on additional control logic.

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