In indoor infrared wireless environment the system performance is affected by the presence of interference from artificial light sources, which can be reduced by employing an electrical high pass filter (HPF). But filtering will result in an interference known as baseline wander. The severity of baseline wander highly depends on the type of modulation technique. This paper discusses the effect of artificial light sources on indoor infrared systems employing dual-header pulse interval modulation (DH-PIM). The paper examines the effect of changing the cut-on frequency of the HPF on the optical power requirement and penalty of diffuse and non-diffuse infrared wireless links for different bit rates. Results presented are compared with other modulation techniques. It is shown that DH-PIM is more susceptible to the effects of baseline wander than pulse position modulation (PPM) and digital pulse interval modulation (DPIM). This is because DH-PIM power spectral density is higher at DC and low frequency region. However, compared with on-and off keying (OOK), DH PIM offers improved performance.
|Journal||The Mediterranean Journal of Electronics and Communications|
|Publication status||Published - Oct 2005|