Electronic device, wireless communication method and computer-readable storage medium
An electronic device comprises a processing circuit configured to: acquire multiple pieces of channel information, which are obtained via multiple channel measurements, about an equivalent channel between a first communication device and a second communication device, wherein in each channel measurement, the second communication device obtains a piece of channel information on the basis of a received reference signal sent from the first communication device, and a reflection signal sent by an intelligent reflecting surface between the first communication device and the second communication device using a corresponding group of reflection parameters to reflect the reference signal; and by means of performing joint processing on multiple groups of reflection parameters used in the multiple channel measurements and the multiple pieces of acquired channel information, determine channel estimations of multiple integration sub-channels which are capable of representing the equivalent channel together with the reflection parameters of the intelligent reflecting surface.
1 . An electronic device, comprising:
processing circuitry configured to:
acquire a plurality pieces of channel information about an equivalent channel between a user equipment and a base station obtained through a plurality of channel measurements, wherein
the electronic device is separate from the user equipment and the base station, and
in each of the plurality of channel measurements, the base station is for acquiring one piece of channel information based on a received reference signal transmitted from the user equipment and a reflection signal sent by an intelligent reflecting surface between the user equipment and the base station reflecting the reference signal based on a set of reflection parameters; and
determine, by jointly processing a plurality sets of reflection parameters utilized in the plurality of channel measurements and the acquired plurality pieces of channel information, channel estimation of a plurality of integrated sub-channels that indicate the equivalent channel together with reflection parameters of the intelligent reflecting surface.
2 . The electronic device according to claim 1 , wherein
the equivalent channel comprises:
a direct link between the user equipment and the base station; and
a reflective link between the user equipment and the base station via the intelligent reflecting surface, and/or
the reflection signal is sent by reflection units of the intelligent reflecting surface after modulating an amplitude and/or a phase of the reference signal according to the reflection parameters thereof.
3 . The electronic device according to claim 1 , wherein
the acquired plurality pieces of channel information comprise a plurality pieces of channel state information of the equivalent channel, and the processing circuitry is further configured to: determine a plurality of channel estimations of the equivalent channel based on the acquired plurality pieces of channel state information, respectively; or
the acquired plurality pieces of channel information comprise a plurality of channel estimations for the equivalent channel.
4 . The electronic device according to claim 3 , wherein
the joint processing comprises:
multiplying an inverse matrix of a training matrix, constructed based on a plurality of extended reflection vectors obtained based on the plurality sets of reflection parameters, by an observation matrix constructed by the plurality of channel estimations, to determine a channel matrix for each of the integrated sub-channels, and
the plurality of extended reflection vectors are obtained by adding a predetermined constant to each set of reflection parameters in the plurality sets of reflection parameters.
5 . The electronic device according to claim 4 , wherein
the intelligent reflecting surface comprises M reflection units and utilizes a set of M reflection parameters corresponding to the M reflection units in each reflection,
M is a natural number greater than 1, and
the processing circuitry is further configured to determine channel matrixes of a total of M+1 integrated sub-channels through the multiplication.
6 . The electronic device according to claim 5 , wherein the number of channel measurements or the number L of sets of reflection parameter is greater than or equal to M+1.
7 . The electronic device according to claim 6 , wherein, in the determined channel matrixes of the M+1 integrated sub-channels, one integrated sub-channel is for indicating a direct link between the user equipment and the base station, and other M integrated sub-channels together with the reflection parameters of the intelligent reflecting surface are for indicating a reflective link between the user equipment and the base station via the intelligent reflecting surface.
8 . A user equipment, comprising:
processing circuitry configured to:
receive a predetermined reference signal sent by a base station via a direct link from the base station to the user equipment and a reflective link from the base station to the user equipment via an intelligent reflecting surface; and
estimate a delay difference between a propagation delay of the direct link and a propagation delay of the reflective link based on a difference between a first reception time at which the predetermined reference signal is expected to be received via the direct link and a second reception time at which the predetermined reference signal is actually received via the reflective link.
9 . The user equipment according to claim 8 , wherein the predetermined reference signal is within a null space of a channel of the direct link.
10 . The user equipment according to claim 8 , wherein
the processing circuitry is further configured to:
determine a transmission time of the predetermined reference signal according to configuration and/or scheduling information of the predetermined reference signal obtained from the base station; and
estimate the first reception time based on the determined transmission time of the predetermined reference signal and timing advance information obtained from the base station.
11 . The user equipment according to claim 10 , wherein the processing circuitry is further configured to transmit delay difference information indicating the estimated delay difference to the base station.
12 . The user equipment according to claim 11 , wherein
the processing circuitry is further configured to:
receive timing advance information from the base station indicating two timing advance values, and
the two timing advance values comprise:
a first timing advance value applicable to the direct link, and
a second timing advance value applicable to the reflective link determined based on the first timing advance value and the delay difference information.
13 . The user equipment according to claim 12 , wherein
each of a first channel from the user equipment to the base station, a second channel from the user equipment to the intelligent reflecting surface and a third channel from the intelligent reflecting surface to the base station is a sparse channel,
the processing circuitry is further configured to:
transmit a first data signal precoded with a first precoding matrix to the base station via the direct link and the reflective link according to the first timing advance value; and
transmit a second data signal precoded with a second precoding matrix to the base station via the direct link and the reflective link according to the second timing advance value,
the first precoding matrix is in a null space of the second channel, and
the second precoding matrix is in a null space of the first channel.
14 . The user equipment according to claim 8 , wherein
the processing circuitry is further configured to:
receive configuration and/or scheduling information of the predetermined reference signal provided from the base station based on the predetermined first reception time.
15 . The user equipment according to claim 14 , wherein the processing circuitry is further configured to:
perform joint signal detection on data signals received via the direct link and the reflective link based on the estimated delay difference, to obtain a data signal sent by the base station.
16 . The user equipment according to claim 14 , wherein the processing circuitry is further configured to:
determine a second timing advance value applicable to the reflective link based on a first timing advance value applicable to the direct link and the estimated delay difference; and
transmit timing advance information indicating the first timing advance value and the second timing advance value to the base station.
17 . The user equipment according to claim 16 , wherein
each of a first channel of the direct link, and a second channel from the base station to the intelligent reflecting surface and a third channel from the intelligent reflecting surface to the user equipment of the reflective link is a sparse channel,
the processing circuitry is further configured to:
receive a joint data signal from the base station device via the direct link and the reflective link, wherein the joint data signal comprises a first data signal precoded by the first precoding matrix and sent according to the first timing advance value and a second data signal precoded by the second precoding matrix and sent according to the second timing advance value;
detect the first data signal from the received joint data signal based on a first signal detection matrix; and
detect a second data signal from the received joint data signal based on a second signal detection matrix, wherein the first precoding matrix is in a null space of the second channel, the second precoding matrix is in a null space of the first channel, the first signal detection matrix is designed such that the third channel is in a null space of the first signal detection matrix, and the second signal detection matrix is designed such that the first channel is within a null space of the second signal detection matrix.