Keyholes in MIMO-OFDM: Train-to-Wayside Communications in Railway Tunnels

Table 1

Main parameters of the MIMO testbed.

Parameter	Symbol	Value
FFT mode	—	2 K
MIMO setup	—	2 × 2
Guard interval	GI	1/8
Scattered pilot pattern		PP1
Frequency		594 MHz
Modulation	—	64 QAM
Sampling frequency		9.1429 MHz
Useful symbol time		2048/ = 224 μs
Guard time		/8 = 28 μs
Symbol time		252 μs
Bandwidth	BW	8 MHz
Code	—	Distributed Alamouti
Data subcarriers		1878
Carrier spacing		4.26 KHz