This paper has presented the different advanced modulation techniques for free space optical (FSO) communication systems transmission efficiency enhancement and signal quality estimation in weak, medium and strong turbulence communication channels. The bandwidth and power efficiency issues in free space optics (FSO) transmissions are addressed under non return to zero on-off keying (NRZ-OOK), r...

DH-PIM modulation as an alternative to other pulse modulation schemes is presented. Its symbol and spectral properties are given. Expressions for slot and packet error rates are presented. Results obtained for the packet error rate are compared with OOK and PIM. It offers the same performance as PIM but considerably better performance compared with OOK.

In this paper DH-PIM modulation scheme and its properties are discussed. Expressions for, symbol length, transmission capacity, bandwidth requirements, photocurrent, power spectral density and slot and packet error rates are presented. Results obtained for the packet error rate are compared with OOK and PIM. It offers the same performance as PIM but considerably better performance compared with...

On–off keying (OOK) has repossessed much new research interest to realize green communication for establishing autonomous sensor networks. To realize ultra-low power wireless design, we investigate the minimum energy per bit required for reliable communication of using OOK in a noncoherent channel setting where envelope detection is applied at the receiver. By defining different OOK channels wi...

OBJECTIVE To review the published literature to evaluate the safety of overnight orthokeratology (OOK) for the treatment of myopia. METHODS Repeated searches of peer-reviewed literature were conducted in PubMed (limited to the English language) and the Cochrane Central Register of Controlled Trials (no language limitations) for 2005, 2006, and 2007. The searches yielded 495 citations. The pan...

We propose a bidirectional wavelength division multiplexing passive optical network (WDM-PON) based on a reflective semiconductor optical amplifier (RSOA) by employing a differential quadrature phase shift keying (DQPSK) signal for down-link and an on-off keying (OOK) re-modulated signal for up-link over 45km SMF colorless WDM-PON without dispersion compensation was demonstrated for both 10 Gbi...

Ultra Wide Band (UWB) wireless systems based on impulse radio have the potential to provide very high data rates over short distances. One of the solutions for the UWB communication systems is the Multi Band On-Off Keying (MB-OOK) which consists in an OOK modulation generalized over multiple frequency sub-bands and associated with a demodulation based on a non-trivial energy threshold compariso...

There are several 60 GHz transceiver architectures that have been explored and reported in the past employing the On Off Keying (OOK) Modulation. All of these designs are primarily based on the conventional bulk CMOS architecture. In this paper, we propose a power efficient double gate (DG) MOSFET based OOK Transmitter in 32 nm DG FinFET technology. The proposed novel OOK modulator consists of ...