Due to its robustness to multipath fading
by transforming a frequency selective fading channel into parallel flat fading channels, OFDM has been adopted in the majority of current and future wireless communications standards such as IEEE 802.15.4 (smart utility network), IEEE 802.11 WiFi, and 4G LTE-A.
Simulation 1: assuming that the multipath number of the received signals is [L.sub.P] = 3 ; the arrival time is [[tau].sub.0] = 100 ns, [[tau].sub.1] = 140 ns, [[tau].sub.2] = 180 ns, respectively; the direction of arrival is [[theta].sub.0] =30[degrees], [[theta].sub.1] =40[degrees], [[theta].sub.2] =60[degrees], respectively; three corresponding complex multipath fading
coefficients are 1, 0.9 and 0.8.
In this example, the controlled channel is a four stream multipath fading
channel, where the attenuation of each path can be individually controlled.
is a consequence of various phenomena, such are atmospheric ducting, ionosphere refraction, and reflection from various objects, causing that randomly delayed, reflected, scattered and diffracted signal components interact and could combine in constructive or destructive manner -.
Recently, the influence of multipath fading
is reported where received OAM modes are examined with antennas near metallic ground plane, where interferences between OAM modes with different eigenvalues are investigated .
In real world scenario, the information signal experiences multipath fading
while propagating through optical wireless channel.
These multipath components are combined vectorially at the receiver, thus resulting in the distortion or fading of the received signal strength, i.e., multipath fading
. That is, the multipath fading
can result in the distortion of RSSI measurements, further reduce the accuracy of distance estimation.
We assume y (t) is RSS of Alice and Bob's multipath fading
It is assumed that the system operates with Quadrature Pahase Shift Keying (QPSK) signaling, and its channel characteristics is frequency selctive multipath fading
By supporting two LoRa Antennas the Kona Macro can utilize antenna diversity to improve receiver performance in the presence of multipath fading
and on the transmit side, multiple transmit channels can be utilized simultaneously resulting in much higher system downlink capacity.
These are then transmitted at the same time keeping the sum of the desired data rate constant, with the property that each of the sub-channels has [T.sub.S] >> [tau] and hence effectively ISI-free channels are obtained and the multipath fading
channel can be seen as flat fading channel for each subcarrier (sub-channels experience relatively flat fading) as shown in Figure 1.
In CWMSN, many factors in practice such as multipath fading
, shadowing, and the receiver uncertainty problem may significantly compromise the detection performance in spectrum sensing.