High-Resolution Uplink Sensing in Millimeter-Wave ISAC Systems

Introduction

This repository provides a demonstrative implementation of the algorithms presented in the paper “High-Resolution Uplink Sensing in Millimeter-Wave ISAC Systems”. The code simulates an uplink sensing framework based on millimeter-wave hybrid arrays, enabling high-precision target parameter estimation.

The simulation generates a scene with $L_s$ static targets and $L_d$ dynamic targets, each with different distances, velocities, and angles of arrival (AoA). The system first performs high-resolution AoA estimation followed by AoA-based 2D-FFT-MUSIC (AB2FM) for target parameter estimation.

Key features of this implementation include:

1. High-resolution AoA estimation using MUSIC algorithm based on frequency domain smoothing.
2. Line-of-Sight (LoS) path detection.
3. Multiple beamforming strategies, including Bartlett beamformer, Null-Space method, SINR optimization method, and hybrid approaches.
4. AoA-based 2D-FFT-MUSIC (AB2FM) algorithm for joint Doppler-delay estimation, enabling accurate recovery of all target parameters (angles, distances, velocities).

The implementation allows for flexible configuration of system parameters and scenario complexity.

Parameters

Basic parameters are defined in Main.m

Ls            = 2;              % Number of static paths
Ld            = 3;              % Number of dynamic paths
L             = Ld + Ls;        % Total number of paths
EbN0_dB       = 10;             % Signal to noise ratio in dB
BF_type       = 'SINR';         % Beamforming type: 'SINR', 'NULL', 'BART', 'HYBD'

Advanced parameters are defined in Params.m

Nr       = 24;     % Number of antennas
Snap_AoA = 50;     % Number of snapshots for Angle of Arrival estimation
Snap_DD  = 10;     % Number of snapshots for Doppler-delay estimation
K        = 32;     % Number of subcarriers
M        = 32;     % Length of each frame (symbols per frame)
Tm       = 1024;   % Interval between two frames (in samples)
fc       = 26e9;   % Carrier frequency, 26 GHz (mmWave band)
D_f      = 100e6 / K;  % Subcarrier spacing (Hz)
Ts       = 1 / D_f;    % Sampling interval (s), equal to symbol duration
c        = 3e8;    % Speed of light (m/s)

Note that L should be less than Nr and K/2.

Result Visualization

MUSIC Spectrum for AoA Estimation

Beam Pattern

2D-MUSIC Spectrum for Doppler-Delay Estimation

Citation

If you use this code in your research, please cite our paper:

@misc{zhao2025highresolution,
      title={High-Resolution Uplink Sensing in Millimeter-Wave ISAC Systems}, 
      author={Liangbin Zhao and Zhitong Ni and Yimeng Feng and Jianguo Li and Xiangyuan Bu and J. Andrew Zhang},
      year={2025},
      eprint={2503.10107},
      archivePrefix={arXiv},
      primaryClass={eess.SP},
      url={https://arxiv.org/abs/2503.10107}, 
}