Int. J. Electron. Commun. (AEÜ) 66 (2012) 855–859 Contents lists available at SciVerse ScienceDirect International Journal of Electronics and Communications (AEÜ) jo ur n al homepage: www.elsevier.com/lo cate/aeue Hata based propagation loss formula using terrain criterion for 1800 MHz Mahdi A. Nisirat a,∗ , Salim AlKhawaldeh b , Mahamod Ismail a , Liyth Nissirat a a Department of Electrical, Electronic and Systems Engineering, Universiti Kebangsaan Malaysia, 43600 UKM Bangi, Selangor Darul Ehsan, Malaysia b EE Department, Faculty of Engineering Technology, Al-Balqa’ Applied University, Jordan a r t i c l e i n f o Article history: Received 28 October 2011 Accepted 4 March 2012 Keywords: Mobile communications Terrain roughness Micro-cells Path loss a b s t r a c t Many mobile propagation models are going under intensive corrections; recently, to suit other new criteria’s such as rough terrain areas. This proposed model modifies Hata main urban equation by adding a formula representing a logarithmic linear regression estimator of the standard deviation () of the measuring campaign path in Amman city, Madaba city, and Jiza town, Jordan. High correlation factor of -96.7% is calculated between excess measured path loss compared to Hata urban path loss and log(). Root mean square error (RMSE) difference between this model and the measured raw data path loss has overcome RMSE calculated for Hata model, by an average of 21 dB, for open areas. The correction of suburban areas is calculated, on average, as 20 dB, and for urban areas as 17 dB. © 2012 Elsevier GmbH. All rights reserved. 1. Introduction Most propagation loss models endeavor, during the initial design procedure, to predict average path loss effectively in diverse landscapes. Such models are intended to help pre-estimate frequency allocation maps, therefore improve overall system reli- ability. Current studies show that most propagation models do not satisfy the precision required in certain locations such as in high rough terrain areas. Recently, many corrections are suggested to cover the need for higher accurate predictions in such landscape sit- uations. Corrections based on real terrain roughness parameters are gaining an interest in order to minimize overall prediction errors in certain rough terrain areas. 1.1. Simple terrain roughness parameters Terrain roughness estimation and description is one of the old sciences used in many applications such as, irrigation systems, fire controlling techniques, sub space terrain acquisition and GPS systems [1]. Terrain relief parameters are to describe simply real roughness of a given area. Slope, curvature, and standard deviation are among these basic parameters [2]. Standard deviation () of the elevation profile is a major of the variability of elevations within a given window size. If the size of the window is similar to the slope length this would be considered a measure of the local relief factor. For a much larger window size, standard deviation is a measure of ∗ Corresponding author. Tel.: +60 1993995507. E-mail addresses: mamnisirat@gmail.com (M.A. Nisirat), skhawaldeh@yahoo.com (S. AlKhawaldeh), mahamod@eng.ukm.my (M. Ismail), liyth@hotmail.com (L. Nissirat). the roughness of a landscape within the specified window size [3]. Fig. 1 clarifies the implication. 1.2. Terrain roughness parameters and path loss estimation Terrain roughness parameters were considered important to achieve the highest accurate path loss prediction models [4]. This is the reason behind the existence of some parameters such as effec- tive transmitter height, effective receiver height, clearance angle, and effective elevation difference between transmitter and receiver in most of the earlier path loss models [5–7]. Although from ter- rain roughness prospective such used parameters barley reflect terrain roughness. This, from the author’s point of view, leads to the assumption that up to the moment terrain description parameters, used in earlier path loss models, were not efficient in reflecting the expected level of roughness accurately. This assumption has high- lighted the need to use more specific terrain roughness parameters and relate these parameters, in some way, with propagation path loss phenomena. In [8] a new method for estimating clutter heights through the evaluation of building elevations is proposed. Losses due to exis- tence of clutter in transmitter–receiver separation area are then predicted. The method basically uses the average level of terrain ground roughness in order to estimate average building heights. The estimation of average ground level roughness depends on the standard deviation of the area between the transmitter and the receiver in an area of 1 km × 1 km, as terrain roughness parameter. Such a method is also recommended in ITU-R P.530 recommen- dations [9]. In [9] terrain roughness of an area is calculated by calculating the standard deviation of terrain heights for an area of 110 km × 110 km for a resolution of 30 s. This value is used in 1434-8411/$ – see front matter © 2012 Elsevier GmbH. All rights reserved. doi:10.1016/j.aeue.2012.03.001