An efficient technique for out-of-band power reduction for the eliminated CP-STC-shaped system for 5G requirements

The most dominant needs for the recent wireless mobile applications are higher bandwidth (BW) efficiency, higher energy efficiency higher quality of services (QOS). The main technique in 4G systems is OFDM but it suffers from some limitations such as large peak to average power ratio (PAPR), higher Out-of-Band (OOB) power radiation, and wasting bandwidth efficiency due to cyclic prefix (CP) extension. In his paper, these OFDM limitations will be reduced with low computational complexity compared to filter bank multicarriers (FBMC). The proposed scheme is based on symbol time compression (STC) for OFDM system. The proposed STC-Shaped system is achieved via interleaver-spreader and symbol shaper in the transmitter side in addition to equalization and combining processes in the receiver side. Comparative study between the proposed system and the conventional OFDM in case of additive white Gaussian noise (AWGN) and COST 207 typical multipath fading channel will be presented. The numerical results show that the proposed STC-Shaped scheme reduces OOB significantly. The proposed scheme improves BER in multipath Rayleigh fading although it is without CP. Thus, the proposed system is more robust against inter symbol interference (ISI) compared to conventional OFDM system. Also, the numerical results show that the PAPR of the proposed system is decreased significantly and also, it is derived theoretically. Also, the proposed scheme overcomes CP extension, and hence increases the bandwidth (BW) efficiency. Finally, the computational complexity for the proposed scheme is derived and it has very low complexity compared to FBMC. The system performance measurments has been fulfilled using cumulative distribution function (CDF), power spectral density (PSD) and bit error rate (BER)

Could the bulbar urethral end location on the cystourethrogram predict the outcome after posterior urethroplasty for pelvic fracture urethral injury?

ABSTRACTObjectives To identify cystourethrogram (CUG) findings that independently predict the outcome of posterior urethroplasty (PU) following pelvic fracture urethral injury (PFUI).Methods Findings of CUG included the location of the proximal end of the bulbar urethra in zones A (superficial) or B (deep) according to its relationship with the pubic arch. Others included the presence of pelvic arch fracture, bladder neck, and posterior urethral appearance. The primary outcome was the need for reintervention either endoscopically or by redo urethroplasty. Independent predictors were modeled using a logistic regression model and a nomogram was constructed and internally validated using 100-bootstrap resampling. Time-to-event analysis was performed to validate the results.Results A total of 196 procedures in 158 patients were analyzed. The success rate was 83.7% with 32 (16.3%) procedures requiring direct vision internal urethrotomy, urethroplasty, or both in 13 (6.6%), 12 (6.1%), and 7 (3.6%) patients, respectively. On multivariate analysis, bulbar urethral end located at zone B (odds ratio [OR]: 3.1; 95% confidence interval [CI]: 1.1–8.5; p = 0.02), pubic arch fracture (OR: 3.9; 95%CI: 1.5–9.7; p = 0.003), and previous urethroplasty (OR: 4.2; 95% CI: 1.8–10.1; p = 0.001) were independent predictors. The same predictors were significant in the time-to-event analysis. The nomogram discrimination was 77.3% and 75% in the current data and after validation.Conclusions The location of the proximal end of the bulbar urethra and redo urethroplasty could predict the need for reintervention after PU for PFUI. The nomogram could be used preoperatively for patient counseling and procedure planning