Cellular antennas were failing due to a signal issue caused by passive intermodulation (PIM). Our engineering team developed a novel solution, working with a leading F1 team to simulate the issue and demonstrate our solution worked. To minimise OPEX costs, Filtronic developed a seed stock, so the upgrade could be a continual process and at the pace required by our customer.

The solution

• Material compatibility issue identified requiring specialised fittings and external consultant validation.
• Quickly built up a seed stock of 100 units. Retrofitted > 100 units per month and upgraded >1k antennas in a year.

The result

• Filtronics agile response, material analysis and diagnostics saved time and cost for our customer.
• Using our highly skilled workforce pool we ramped production and assembly to meet customer demand.

The challenge

• Cellular antennas were failing due to a signal issue caused by passive intermodulation (PIM).
• PIM occurred in hot and humid locations.
• This worsened where the antenna was using multiple bands.

Time was critical in this instance, as it addressed an issue that could be imminent and if it did become an issue the disruption would have been significant and far-reaching. There was a real concern that LTE could interfere with terrestrial TV. To mitigate the risk, Filtronic developed a customised digital tv filter rapidly that could be installed locally by the user. The production ramp on this was from zero to >30k units per week in less than 4 weeks. Due to the experience of our engineering team, we were able to meet a design window of a couple of months for all variants (6 products in total).

The solution

• Product developed to be able to be sent via standard post and installed locally by the user.
• Product ramped up within 3-4 weeks from nothing to >30k units per week.

The result

The challenge

• LTE could potentially interfere with terrestrial tv band.
• To mitigate the perceived risk the filter could be rapidly deployed country wide.

We maintained our customers’ market position by working agilely, even when their supply chain was severely disrupted. Value engineering component choices, such as surface-mounted coaxial connectors, helped Filtronic deliver an E-Band transceiver solution on time and at a lower cost. In addition, we implemented improved design approaches, including circuit optimisation, to mitigate chipset variability.  

The solution

• Rapidly designed to meet existing physical footprint and interface requirements.
• Applied our client’s own E-band chip set.
• Design to launch was approx. 6 months.
• Product was launched straight into production with high yield.

The result

• High yield minimised impact, reduced their costs to transfer.
• Imposed much needed quality controls into the client’s supply chain.
• Mitigated raw material variation risks (vastly reducing the cost of quality) and quickly ramped the product, minimising supply impact to our client’s end customers.

The challenge

• A USA E-band radio specialist specialising in enterprise markets such as private/campus networks and high frequency trading.
• Their existing supply chain was disrupted when their prime supplier went out of business.

Our solution supported the nationwide rebanding of the 800MHz spectrum to facilitate the removal of analogue TV bands and the rollout of digital TV. This was a unique challenge that required a customised solution and could have only been delivered by a manufacturer with a rich history within the 700MHz and 800MHz bands. Our customer wanted a rapid solution for a remotely configurable filter This was successfully delivered representing OPEX saving of $,000’s per site, multiplied across 17,000 sites across the network, delivering total savings of >$10m.

The solution

• Experience and track record within 700MHz and 800MHz enabled rapid development of a remotely configurable filter.
• Cost was significant driver, so was integral to the design considerations.
• The filter utilised built-in motors which adjusted tuning through the AISG port.
• Advantages for client was they did not have to send engineer to site

The result

• Reduced hardware costs and installation efficiency.
• The site construction teams could enable/disable the notch functionality remotely.
• Delivered OPEX savings of $,000’s per site, multiplied across 17,000 sites in the network delivered savings > $10m.

The challenge

• Tier 1 OEM of wireless network infrastructure.
• Their client, a major US Mobile Network Operator
• High power, PIM critical (careful design considerations given)
• Creating high power within a compact envelope.
• Support a nationwide rebanding of the 800 MHz spectrum.

Street furniture is an everyday part of our lives but adding additional elements can be contentious. Filtronic developed a retrofittable cross-band combiner for existing locations with no additional visual pollution. The challenge was space within the existing cabinets and due to planning restrictions, no additional cabinets were allowed. With 12 feeder cables already in each pole and a pole that was shared with another mobile network operator that could not be cut, Filtronic developed a modular ring-mounted system that could be deployed fast with only minor site customisation.

The solution

• Developed a modular “ring” mount system, that could be installed via the services hatches in the pole.
• Maintained physical integrity while delivering RF requirements.
• Concealed telecom filters internal to utility pole.
• Retrofit into existing locations with minor modifications.
• Designed a mounting ring that could be split into two.

The result

• Fast site deployment, as only minor tweaks were required to enable mass rollout.
• Improved and streamlined the installation process.
• No visual pollution, keeping the street furniture intact and reduced ongoing costs as retrofittable.

The challenge

• Major 3^rd party site operator, the pole was shared with another MNO.
• Discrete radio head combining within an 11” dia. pole.
• Improve system operation and site aesthetics.
• Ability to field modify was critical.

By proactively working with its leading OEM client, Filtronic was able to meet its business objective of re-shoring critical product assembly and supply chain back to the USA to improve equipment lead times. Filtronic successfully re-located manufacturing of the finished product from its offshore facility to its established operations in Salisbury, Maryland. Utilising its experience, local knowledge and a cloud-based Manufacturing Execution System (MES) platform, this complex transition was managed smoothly, effectively and efficiently.

The solution

• Successfully commissioned a full US-based assembly facility.
• Achieved  client’s quality standards. 
• Passed an extensive and rigorous customer audit.
• Full expedited re-certification.

The result

• Entire re-shoring operation delivered within the clients time frame of <6 mths.
• Implemented product and process improvements, improving workflow and logistics
• Significant reduction in lead time.

The challenge

• Re-located manufacturing of the finished product.
• Fulfilling all the key customer’s requirements during the transition.
• Complex transition was managed smoothly, effectively and efficiently.

Our customer had limited space to run the additional coax cables required to transport the GPS signal from the base station to the antenna. Filtronic leveraged its filter design experience to develop a combiner that utilised the existing telecom coax, with minimal addition to the GPS noise figure. With its small size, low loss, and transparent operation, the PXC021 GPS/Cellular Combiner is an effective means to combine GPS L1 & L2 carriers with a wide spectrum range of other RF frequencies.

The solution

• Developed a combiner which utilised existing telecom coax.
• Created a versatile, low-cost method to transport the GPS signals from the base station to the antenna.
• No additional long cable runs.
• Minimal addition to GPS system noise figure.

The result

• Transported the GPS signals efficiently and reduced cost.
• Streamlining the combiner, combining all cellular/LTE frequencies and both GPS bands.
• Excellent cellular to GPS isolation (>55 dB).

The challenge

• Our client is a Tier 1 provider of fibre and neutral host tower and site solutions.
• GPS timing solution for in-building distributed antenna systems.
• Limited space available to run additional coax cable through vertical risers.

Our MES (Manufacturing Execution System – MARS) gave Filtronic an early warning of a potential problem with a newly qualified component. The issue was isolated and the root cause was determined before deployment by Filtronic, substantially reducing operating costs. 

The solution

• Our team embedded in our client’s facility.
• Qualified a replacement part in record time.
• Repaired all non conforming parts.

The result

• Minimised any disruption, saving time and money through eliminating transport costs.
• Client was able to maintain delivery commitments.

The challenge

• Acting expediently and rapid component qualification.
• Identify and quarantine non-conforming parts via MES.

We were approached by a leading P25 OEM who wanted a high-performance combiner solution that would remain maintenance-free for over 25 years, minimising their ongoing OPEX. Because of Filtronic’s extensive expertise in filter design, we were able to use advanced custom ceramics to ensure the thermal targets were reached, resulting in high reliability with no recalls despite having over 16k on the market.

The solution

• Industry standard active temp comp not reliable enough.
• R&D team developed passive temp comp using progressive series of advanced custom ceramics.
• Linearity over temperature exceeded customer requirements.

The result

• Client overrode standard protocol and selected us as single source due to performance & reliability advantage.
• Established reliability with no recalls.
• Over 16,000 combiners shipped since 2004
• Built in USA.

The challenge

• The mean time between failure needed to be at least 900,000 hours for the first 10 years of operation.
• Peak instantaneous power capability 9,000W.
• Requirement to be stable and maintenance free for 25+ years.

A leading defence prime approached Filtronic to design a drop-in replacement for an obsolete filter due to component obsolescence. As this use case was generally used for emergency relief, deployment speed was critical. A drop-in replacement is inherently challenging since you are dealing with an existing package footprint, but Filtronic’s solution worked seamlessly within the customer’s existing package.

The solution

• Improve RF performance whilst replacing obsolete product.
• Accelerated development time.
• Rigorous modelling proved technical approach worked.

The result

• Reduced lead time for improved availability.
• Meeting the environmental specification.

The challenge

• Drop in replacements are inherently challenging as you already have a high level of existing architecture.
• Challenging environmental conditions including temperature, altitude, shock and vibration.
• Speed of deployment was very important, as this use case was generally used in emergency relief situations.