Communications Audit UK
RF Receiver Products
Communications Audit UK (CommsAudit) is a manufacturer and integrator of high-quality RF receiver products, and a specialist in demanding and complex RF engineering projects. We work on all aspects of RF system design, from the RF baseband through to microwave frequencies.
CommsAudit has extensive experience of high-performance radio communications and telecommunications solutions. It is the only British-owned company specialising in HF, VHF and UHF receiver systems. CommsAudit can provide:
- System design, analogue circuitry, RF baseband through microwave frequencies
- Digital hardware, embedded controllers, microprocessors to Linux networked solutions
- Extensive experience in digital communications methods
- Development of security sensitive embedded control and monitoring system applications
- Remote GUI for data display/analysis, system control and BITE
CommsAudit manufactures RF and digital equipment covering the frequency range 10kHz to 6GHz, including digital control and DSP. In addition CommsAudit can produce bespoke ‘special-to-task’ equipment.
HF narrowband tuner digitiser
The high-frequency narrowband tuner digitiser system is a high-performance eight-channel tuner solution providing frequency coverage from 2MHz to 30MHz. The system is capable of operating in a hostile high signal RF environment and provides superior performance with its excellent spurious free dynamic range (SFDR), in particular when compared with a wideband tuner approach. Each system has eight independent tuners packaged within a 2U rack mount enclosure and is ideal for space limited applications.
The system can be used to replace legacy HF receivers in a number of RF communication surveillance and collection applications, and has been engineered to allow for future proofing and changes, such as including the implementation of the VITA-49 standard when ratified. The design is approved to MIL-STD-461E and MIL-STD-462 standards. CommsAudit is also providing, as an option, a comprehensive software suit of control and operational applications.
Antenna matrix switching unit
This 2U unit is a fast switching antenna matrix switching unit with four inputs and eight buffered outputs arranged in a full fan-out, non-blocking architecture. The HF variant is designed to switch the signals from four antennae through a non-blocking full fan-out switching matrix in a multiple HF receiver system.
Providing eight receiver outputs, each of the receiver outputs can select any of the inputs without any restrictions. Using high intercept point solid-state switch technology, the switch matrix provides a step forward in RF antenna switching matrix technology and is one of a series of HF/VHF/UHF units available from CommsAudit. The series of HF switch matrix units can be supplied with a number of input and output channels up to a maximum of 16-inputs and 32-outputs, although multiple matrices can be employed for larger receiver systems.
HF antenna switch matrix system
The CommsAudit fast-switching antenna switch matrix system comes with hot-swap capability. It has 48 inputs and 64 outputs arranged in a full fan-out, non-blocking architecture. This high-performance matrix is housed in two 46U 19in rack cabinets.
The antenna switch matrix system has triple hot-swap power supplies in each rack and dual independent controlling computers to minimise catastrophic failure. In the event of a 24V power supply, computer or communications failure, the antenna switch matrix will continue to function with a minimum of 50% of the system outputs available. In addition all RF cards are hot-swap compliant.
The RF input signal is protected from high amplitude pulses by a combination diode protection circuit. The signal is routed through a power splitter before it is fed to one of six matrix switching units. Each matrix switching unit has 16 inputs and 32 independent outputs. The switched outputs are then combined by two amplified 96 x 32 SP3T switch units to provide the required 64 system outputs. CommsAudit is currently adapting this to provide a 64 in / 64 out matrix system.
Wideband receiving multicouplers
The CommsAudit wideband receiving multicouplers (200kHz-32MHz) use highly balanced push-pull amplifiers in their design to provide excellent second and third order intercept points in the presence of high level interference signals. The antenna input has lightning and static protection as standard with a combination N-type and EMP protection device. Each multicoupler consists of a standard 483 mm (19in) rack-mounted unit and has a panel height of 1U, 2U or 3U depending on the number of output ports. Each output has a buffer amplifier to assist with isolation and receiver matching.
Antenna beamformer system
The CommsAudit antenna beamformer system is a very high-performance antenna multicoupler system with integral delays suitable for antenna beam forming. The system takes the multiple antenna feeds and provides lightening protection for follow-on subsystems.
After filtering, the signal path enters a very high dynamic range, low noise amplifier before being split. The signal paths are fed into phase delay networks and then combined to form the required antenna beams. These outputs are distributed by a set of high linearity line driver amplifiers, whose outputs are also monitored for signal level faults and reported via the local and remote BITE displays.