T-Mobile's 6 Carrier Aggregation and Throughput Tue, Jan 09, 2024

On January 4th, Fierce Wireless posted a story on T-Mobile's six component carrier aggregation test with Ericsson and Qualcomm.  6 Carrier Aggregation, also known as 6CA, is a cutting-edge technology that allows mobile carriers to combine multiple frequency bands to increase network speed and capacity. By aggregating six carriers, T-Mobile can deliver faster download and upload speeds, reduced latency, and improved overall network performance.

What was interesting in the article from a spectrum expert standpoint are the details they included and the details that were left out.  Let's first look at the details that were included:

I am going to use our current Mobile Carrier - Spectrum Ownership Analysis Tool to determine the markets where T-Mobile has two blocks of PCS spectrum, two blocks of AWS spectrum and two blocks of 2.5GHz spectrum. 

Using the NR Channel Analysis Module, the specific 3GPP channels that are available for T-Mobile's spectrum in a particular county are displayed by NR band.  In the image below, we have filtered to display counties where T-Mobile holds two blocks of n25 spectrum and two blocks of n66 spectrum.

Channel Analysis - FDD Downlink:

This filter also included 2.5 GHz spectrum.  I wanted to find counties with both a 100 MHz channel and a 90 MHz channel to get the maximum throughput.

Channel Analysis - TDD:

I'm not quite sure how they arrived at 245 MHz for the combined spectrum.  If I only look at the FDD Downlink and the TDD spectrum, I can get 245 MHz with the configuration below..  This configuration is available to T-Mobile in 69 counties.

To get the estimated composite channel throughput values, we have modeled 4x4 MIMO antennas with 256QAM modulation in our Throughput Analysis Tool, which is part of the Channel Analysis Module

Throughput Analysis - FDD Downlink:

Throughput Analysis - TDD Downlink Timeslots:

Throughput Summary:

Although I ended up with a higher throughput than was achieved in the test call, my throughput values are theoretical and would be reduced by real world conditions such as distance to the cell site and the achievable modulation.