Pulse Electronics - LTE

Pulse Electronics Develops Unique, Software-based Design Optimization Process for LTE Small Cell Base Station

 

Company Profile

Pulse Electronics develops electronic components for the wireless and wireline communications, power management, military/aerospace, and automotive industries that help customers build the next great product by providing the needed technical solutions. Pulse has a long operating history of innovation in magnetics, antennas, and connectors, as well as the ability to ramp quickly into high-quality, high-volume production. Previously, the holding and operating companies were known as Technitrol, Inc. and Pulse Engineering, respectively. Pulse is a participating member of IEEE, ATIS, ETSI, HDMI, the DSL Forum, CommNexus, and MoCA.

The Design Challenge

Pulse Electronics was developing a maximum efficiency LTE small cell base station with an operating frequency of LTE Band8, 880-960MHz. Pulse’s work on small cellular base station antennas includes using directional patch radiators with two feed ports that have vertical and horizontal polarizations.

When designing antennas for base stations and mobile devices, an essential step of the design process is to ensure that the antenna resonates at the correct operation frequencies. Traditionally, the input impedance of an antenna is tuned by changing the antenna dimensions until the desired operational frequencies have been obtained. This is a time-consuming, costly, and inefficient approach.

The Solution

While patch antennas are commonly known and widely used throughout the antenna industry, Pulse’s use of modern design tools has introduced a new, unique, software-based design optimization process in which the input impedance of the antenna is tuned much more quickly and efficiently than changing the actual dimensions of the antenna. Instead, Pulse designers use an external circuit-matching tool for the inductors, capacitors, and transmission lines. They are able to design, tune, and optimize their antenna systems through a combination of AWR’s Microwave Office® circuit design software and Optenni’s Optenni Lab matching circuit generation and antenna analysis software. The end result of this cross-company design flow yields a higher performing product, a more cost effective design, and faster time to market.

The antenna for this LTE base station project was simulated with a target bandwidth of 880-960MHz using AWR’s Analyst™ 3D electromagnetic (EM) simulator within Microwave Office. For this design, a full 3D EM simulator was necessary given that the feed lines were supported by a narrow printed circuit board (PCB) substrate with such finite dielectrics that edge couplings had to be accounted for. Next, Optenni Lab software was employed for the matching circuit design for Port 2. Optenni Lab provides an easy-to-use interface for direct optimization of antenna efficiency that accounts for optimization over a wide range of vendor libraries, tolerance analysis, and more.

Within a matter of seconds, Optenni Lab provided multiple optimized matching circuit topologies. The resultant matching circuit was synthesized to maximum efficiency over the band. The remaining fine-tuning steps involved included the layout details for placement of the discrete components. Finally, the antenna prototype was manufactured and measured at Pulse. The agreement between the simulations and measurements was good.

Why Did You Choose AWR?

Pulse has been using the APLAC® harmonic balance simulation engine for over a decade and when APLAC became part of AWR, Pulse upgraded to the Microwave Office design environment to take advantage of additional AWR technologies, which have proven to be key in the success of its designs. Pulse designers have been very happy with the accuracy of AWR’s models and speed of its simulation engines. The ability to use Optenni Lab within the circuit environment has provided Pulse with a “first-time-right” virtual software design methodology and matching circuit design. AWR has helped Pulse develop a unique, optimal design and simulation solution that meets the design team’s need for this highly demanding LTE base station antenna application.

The full application note is available at www.awrcorp.com/solutions/technical-papers