Code and data for "Ultra -compact quasi-true-time-delay for boosting wireless channel-capacity"

This simplified code should run on any recent MATLAB version. No non-standard hardware is required.
Instructions for installation are found on the MathWorks website, using a student, commercial or trial license.
Installation time for MATLAB R2021a is about 10 minutes. Run the editor (green triangle). Run time for each code is <4 seconds.

The code reproduces the analysis in Figure 4 and Supplementary Figure 12 
A)  MATLAB code that uses the parameters in the main text to plot the channel capacity vs signal bandwidth (Fig 4c) 
for the three types of delay elements. The same code is provided thrice for different signal-to-noise-bandwidths (2,5 and 10 GHz) 
and should reproduce the plots in Fig. 4c when run.
These are combined when presented in Fig 4c of the main text.

The antenna_gain.m function should be run within the same folder as channel capacity code.  The code files in the "Channel capacity code" folder are
1.    Code_Channel_capacity_for_arrays_Fig_4c_noise_density_2_GHz.m
2.    Code_Channel_capacity_for_arrays_Fig_4c_noise_density_5_GHz.m
3.    Code_Channel_capacity_for_arrays_Fig_4c_noise_density_10_GHz.m
4.    antenna_gain.m

B) MATLAB code that uses the parameters in the main text to Projected Array Factor (AF) for the three types of delay elements,
a measure of the arrays' gain in a target angle-of-arrival. 
The code for this section is provided in "Array Factor code" folder with the following files. No additional functions are required.
1.    Array_factor_vs_angle_phase_shifter.m
2.    Array_factor_vs_angle_quasi_true_time_delay
3.    Array_factor_vs_angle_true_time_delay

C) MATLAB code that analyzes the frequency response by plotting the array factor vs the in-band frequencies (Fig S.12 c) to show the poor fidelity 
of phased array across a broad bandwidth and more importantly, to show that there is minimal loss of directive gain using a Q-TTD array. 
The additional relevant code is 
4.    Array_factor_vs_Frequency_Phase_Shifter
5.    Array_factor_vs_Frequency_quasi_true_time_delay.m
6.    Array_factor_vs_Frequency_true_time_delay.m
We also include the channel capacities (that the code should now reproduce) for three signal-to-noise-power-densities for the three types of arrays, for ease of comparison with array factor (Fig S.12 d).

Data for IP3 measurements, phase measurements states and loss (including worst cases) are in the "Source data for Quasi True Time Delay element.xlsx" file