Conceitos essenciais
A novel two-step closed-loop approach is proposed to effectively emulate typical 3GPP 5G channel models in a reverberation chamber environment for over-the-air compliance testing.
Resumo
The paper presents a novel two-step closed-loop method for accurate simulation of 3GPP 5G channel or SCME channels in a reverberation chamber (RC) environment. The key aspects are:
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Channel Measurement Step:
- A high-accuracy channel sounder system is developed to capture the wireless channel characteristics of the RC.
- An equalizer filter is derived from the measured channel impulse response (CIR) of the RC.
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Channel Model Synthesis Step:
- The protocol-compliant RF signal is convolved with the equalizer filter before passing through the channel emulator (CE).
- The CE introduces the multipath fading and Doppler spread according to the target 3GPP channel model.
- The output signal from the CE then goes through the RC, and finally to the receiver for performance evaluation.
Measurement results demonstrate the effectiveness of the proposed approach in emulating typical 3GPP 5G channel models, such as Pedestrian-B and TDL-B, even with the limited channel sampling rate of the CE. The method enables extending the use of RCs for performance tests defined in standards like 3GPP.
Estatísticas
The reverberation chamber has dimensions of 6.55 m × 5.85 m × 3.5 m.
The channel sounder system uses a pair of National Instrument (NI) vector signal transceivers (VSTs) PXIe-5840 with up to 1 GHz RF bandwidth.
The channel emulator is based on the vector signal transceiver PXIe-5644R with a 100 MHz channel sampling rate.
Citações
"The inherent long decay power delay profile (PDP) in the reverberation chamber (RC) is a major challenge for accurate channel emulation of 3GPP channel model, which is widely used in performance test of the physical layer."
"The effectiveness of the cancellation can be impressively high under the assumption of the introduced artificial path with a very short delay value to the true path, such as 0.1 ns. However, because of the limitation of the CE implementation, minimum available delay interval between the true path and artificial path is usually limited by the maximum available channel sampling rate and RF bandwidth of the CE."