5.3 Simulation results

First, a simulation experiment for the delay elements of PIC-based OBM (see Figure 13) was carried out. Table 6 lists the results of phase error values for the center and two extreme frequencies of the RF generator.

Then, a simulation experiment for the PIC-based 88 OBM (see Figure 14) was carried out when the output of EA was alternately connected to each input of OBM, and at each point, the RF generator was sequentially tuned to the frequency of each


Table 6.

The simulation results of phase error values at the outputs of OBM under test.

Design of Reconfigurable Multiple-Beam Array Feed Network Based on Millimeter-Wave… DOI: http://dx.doi.org/10.5772/intechopen.89076

downlink channel. Table 7 exemplifies the simulation results of phase error values for channel A6 (see Figure 16) at the corresponding outputs.

Finally, a simulation experiment for the mmWave multiple-beam array feed network of Figure 16 was carried out. Figure 17 exemplifies the calculation results of the back-baffled normalized radiation patterns generated at the central and two extreme frequencies of the input RF band based on the data for the amplitude and

Figure 17.

Normalized radiation patterns for the mmWave multiple-beam array feed network under test (a) at 39.5 GHz (b) at 38 GHz (c) at 40.5 GHz.

The module of Figure 15 contains a set of PIC library models, such as two Y-branches (YB), four straight waveguides (SW) including two SW for 90° phase shift, and two compensating SW with equivalent phase shift of 360°, six 90° waveguide bends (WB), one waveguide crossing element (WC), and two

The model and setup for simulation of mmWave multiple-beam array feed network.

array feed network under study that contains the model of 88 OBM (see Figure 14) with six inputs because as shown in subsection 3.1, the extreme beams generated by the Butler matrix (A2 and A7 in Figure 3) have a significantly greater width and less directivity than the others do (see Figure 4). In addition, there are two instrumental library models in the setup. The first one imitates optical transmitting module including library models of laser source and six optical modulators controlled by six RF generators, the RF carriers of which are allocated in the band of 38.0–40.5 GHz. The second one imitates optical receiving module including library models of eight PIN photodiodes and eight RF network analyzers recording amplitude and phase RF signal distributions at the photodiode outputs. One can see their

Finally, Figure 16 depicts the model and setup for the mmWave multiple-beam

First, a simulation experiment for the delay elements of PIC-based OBM (see Figure 13) was carried out. Table 6 lists the results of phase error values for the

Then, a simulation experiment for the PIC-based 88 OBM (see Figure 14) was carried out when the output of EA was alternately connected to each input of OBM, and at each point, the RF generator was sequentially tuned to the frequency of each

Reference phase shift 22.5° 45° 67.5° 90° Equivalent lengths (mm) 0.215 0.437 0.662 0.883 Error value At the center RF 0.1° 0.2° 0.4° 0.5°

> At the lowest RF 1° 2° 3° 4° At the upper RF 1° 2° 3.1° 4.1°

X-couplers (XC).

Advances in Array Optimization

Figure 16.

relevant parameters in Tables 4 and 5.

center and two extreme frequencies of the RF generator.

The simulation results of phase error values at the outputs of OBM under test.

5.3 Simulation results

Table 6.

126


simple possibility of reconfiguring the antenna system in two directions: frequency

This work was supported by the Russian Foundation for Basic Research, Grants

reconfiguration due to the rearrangement of the RF synthesizer and spatial reconfiguration due to the introduction of a multichannel optical switch at the input. As a result of the simulation experiments performed using VPIphotonics Design Suite and MATLAB software, for both the integrated optical Butler matrix itself and the beamformer based on it, an acceptable quality of beams formation in a

Design of Reconfigurable Multiple-Beam Array Feed Network Based on Millimeter-Wave…

particular 5G pico-cell was obtained.

DOI: http://dx.doi.org/10.5772/intechopen.89076

No. 17-57-10002 and No. 18-29-20083.

The authors declare the lack of "conflict of interest."

Mikhail E. Belkin\*, Dmitriy A. Fofanov, Tatiana N. Bakhvalova and

MIREA—Russian Technological University, Moscow, Russia

\*Address all correspondence to: belkin@mirea.ru

provided the original work is properly cited.

Scientific and Technological Center "Integrated Microwave Photonics",

© 2019 The Author(s). Licensee IntechOpen. This chapter is distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/ by/3.0), which permits unrestricted use, distribution, and reproduction in any medium,

Acknowledgements

Conflict of interest

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Alexander S. Sigov

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