1 Ocak 2024 Dergi makalesi Açık Erişim

Ahmadi, Mohammad Javad; Kazemi, Mohammad; Duman, Tolga M.

Citation Style Language JSON

{
  "DOI": "10.1109/TWC.2023.3288376", 
  "abstract": "<p>We study the problem of unsourced random access (URA) over Rayleigh block-fading channels with a receiver equipped with multiple antennas. We propose a slotted structure with multiple stages of orthogonal pilots, each of which is randomly picked from a codebook. In the proposed signaling structure, each user encodes its message using a polar code and appends it to the selected pilot sequences to construct its transmitted signal. Accordingly, the transmitted signal is composed of multiple orthogonal pilot parts and a polar-coded part, which is sent through a randomly selected slot. The performance of the proposed scheme is further improved by randomly dividing users into different groups each having a unique interleaver-power pair. We also apply the idea of multiple stages of orthogonal pilots to the case of a single receive antenna. In all the set-ups, we use an iterative approach for decoding the transmitted messages along with a suitable successive interference cancellation technique. The use of orthogonal pilots and the slotted structure lead to improved accuracy and reduced computational complexity in the proposed set-ups, and make the implementation with short blocklengths more viable. Performance of the proposed set-ups is illustrated via extensive simulation results which show that the proposed set-ups with multiple antennas perform better than the existing MIMO URA solutions for both short and large blocklengths, and that the proposed single-antenna set-ups are superior to the existing single-antenna URA schemes.</p>", 
  "author": [
    {
      "family": "Ahmadi", 
      "given": " Mohammad Javad"
    }, 
    {
      "family": "Kazemi", 
      "given": " Mohammad"
    }, 
    {
      "family": "Duman", 
      "given": " Tolga M."
    }
  ], 
  "container_title": "IEEE TRANSACTIONS ON WIRELESS COMMUNICATIONS", 
  "id": "280643", 
  "issue": "2", 
  "issued": {
    "date-parts": [
      [
        2024, 
        1, 
        1
      ]
    ]
  }, 
  "page": "13", 
  "title": "Unsourced Random Access Using Multiple Stages of Orthogonal Pilots: MIMO and Single-Antenna Structures", 
  "type": "article-journal", 
  "volume": "23"
}