On RPI latest version Kernel observed connectios dromps with RTL8xxxU driver for RTL8192EU module.
dowload this module for 4.14.42 kernel
ssh login
cd /usr/src/
wget https://raw.githubusercontent.com/sparky-sbc/sparky-test/master/rpi-41442-8192eu/8192eu.ko -O /lib/modules/4.14.42-v7+/kernel/drivers/net/wireless/8192eu.ko
depmod -a
modprobe 8192eu
configure Wi-Fi