We present the four-dimensional volumetric electromagnetic field measurements (x, y, z and frequency) of the complex radiated field produced by an 8-element circular antenna array. The array is designed to produce a Laguerre–Gauss (LG) mode l = +1 over the frequency range of 9–10 GHz. We evaluate our findings in terms of far-field LG mode purity and spectral efficiency in terms of the quadrature amplitude modulation (QAM) modulation scheme that can be supported. The application of LG modes in radio systems is as a means of multiplexing several data streams onto the same frequency, polarization and time slot, thus making a highly spectrally efficient transmission system or enhancing radar systems by means of exploiting mode behaviour as an additional degree of freedom. Our results show that for the circular antenna array, we find that mode purity is sufficient to support binary phase shift keying or quadrature phase shift keying modulation over a 0.3 GHz bandwidth, which corresponds to a spectral efficiency of 1.5 b s⁻¹ Hz⁻¹ per mode. Closer to the antennas' design frequency, 256QAM modulation may be supported over a 0.05 GHz band, and which corresponds to a spectral efficiency of 11 b s⁻¹ Hz⁻¹ per mode. We anticipate the practical insights provided in this paper contribute to the successful design of such systems.

我们介绍了8元素圆形天线阵列产生的复杂辐射场的三维体积电磁场测量值（x，y，z和频率）。该阵列被设计成产生一拉盖尔-高斯（LG）模式升=在9–10 GHz频率范围内为+1。我们根据可以支持的正交幅度调制（QAM）调制方案评估远场LG模式纯度和频谱效率方面的发现。LG模式在无线电系统中的应用是将多个数据流多路复用到相同的频率，极化和时隙上的一种手段，从而通过利用模式行为作为附加的程度来构成频谱高效的传输系统或增强雷达系统。自由。我们的结果表明，对于圆形天线阵列，我们发现模式纯度足以支持0.3 GHz带宽上的二进制相移键控或正交相移键控调制，这对应于1.5 bs ^-1 Hz ^-1的频谱效率每个模式。接近天线的设计频率，可以在0.05 GHz频带上支持256QAM调制，这对应于每个模式11 bs ^-1 Hz ^-1的频谱效率。我们期望本文提供的实践见解有助于此类系统的成功设计。