เปรียบเทียบวิธี

	แบบจำลองการแพร่กระจายคลื่นแบบ Ray Tracing	ระบบอินพุตเอาต์พุตหลายหน่วย (Multiple-Input Multiple-Output: MIMO)	การแบ่งความถี่แบบออร์โธโกนอล (Orthogonal Frequency Division Multiplexing - OFDM)	ZF/MMSE Equalization
สาขาวิชา	โทรคมนาคม	โทรคมนาคม	โทรคมนาคม	โทรคมนาคม
ตระกูล	Process / pipeline	Process / pipeline	Process / pipeline	Process / pipeline
ปีกำเนิด	1993	1995	1971	1974
ผู้ริเริ่ม	Maciel, Bertoni, and Xia	Telatar, Foschini, and Gans	Weinstein and Ebert	Saleh Mansour and Paul Zervos
ประเภท	deterministic propagation algorithm	spatial multiplexing technique	multicarrier modulation scheme	linear equalization algorithm
แหล่งต้นตำรับ	Maciel, T. F., Bertoni, H. L., & Xia, H. H. (1993). Unified approach to prediction of propagation over buildings for all ranges of frequencies. IEEE Transactions on Vehicular Technology, 42(1), 41-45.	Telatar, I. (1999). Capacity of multi-antenna Gaussian channels. European Transactions on Telecommunications, 10(6), 585-595.	Weinstein, S. B., & Ebert, P. M. (1971). Data transmission by frequency-division multiplexing using the discrete Fourier transform. IEEE Transactions on Communication Technology, 19(5), 628-634.	Proakis, J. G. (2001). Digital Communications (4th ed.). McGraw-Hill.
ชื่อเรียกอื่น	deterministic propagation, site-specific modeling	spatial multiplexing, antenna diversity	multicarrier modulation	channel equalization, interference cancellation
ที่เกี่ยวข้อง	4	5	5	5
สรุป	Ray tracing is a deterministic propagation modeling technique for predicting electromagnetic field strength at specific locations. Instead of empirical formulas (like Okumura-Hata), ray tracing traces paths of electromagnetic energy as it reflects, diffracts, and scatters off buildings and terrain. With accurate 3D geometry and material properties, ray tracing predicts site-specific path loss, multipath delay profiles, and angle of arrival, making it ideal for detailed coverage planning, interference analysis, and system design. Ray tracing is now standard in professional cellular planning tools.	MIMO is a technique that uses multiple transmit and receive antennas to significantly increase channel capacity and reliability. Pioneered theoretically by Telatar (1999) and Foschini & Gans (1998), MIMO exploits multipath propagation—typically a liability in wireless—as an asset by creating independent spatial channels. It is now fundamental to all modern wireless systems including LTE, WiFi-6, and 5G, where it provides both capacity gains through spatial multiplexing and robustness through diversity.	OFDM is a multicarrier modulation technique that divides a wideband channel into many narrowband orthogonal subcarriers. Introduced by Weinstein and Ebert in 1971, it exploits the duality between time and frequency domains to efficiently use spectrum while mitigating intersymbol interference in frequency-selective channels. OFDM is now the standard for high-speed wireless systems including WiFi, cellular LTE, and digital broadcasting.	Zero-Forcing (ZF) and Minimum Mean-Square Error (MMSE) equalization are fundamental linear receiver algorithms for combating intersymbol interference in dispersive channels. Developed in the context of data transmission theory, these methods form the basis of modern channel equalization in wireless and wired systems. While ZF aggressively cancels interference, MMSE balances interference suppression with noise enhancement, making it the optimal linear solution under Gaussian noise.