Introduction

Classically, intermediate frequency (IF) data passes between system elements in analog format over coaxial cables. Our group is creating a new interconnect standard for passing IF data between system elements in a digital format.

Our members target defense applications. Our team will create and publish a standard for use within defense applications. This standard will be link agnostic, that is, not targeted towards any specific physical link implementation. Additional later standards may layer above the Serial Front Panel Data Port (sFPDP) standard which is ANSI/VITA 17.1-2003 supplemented by working draft VITA 17.2, or other physical transports, possibly USB or IEEE 1394 for applications that require only simple systems. We hope to submit our standards into the ANSI/VITA process to stimulate adoption by the broader commercial community. We are particularly interested in stimulating adoption by the defense COTS industry.

Our group is also monitoring work within the OMG's Software-Based Communications DTF (formally the Software Radio DSIG). They sponsor a project to define a software API that will control the intermediate frequency data streams that will pass over our new interconnect standard. One presentation from that DTF is available from our own Public Documents page.

Scope of Effort

The working group will produce a standard that will define a methodology for using data packets to convey digitized analog signals among RF communication receiver/transmitters and digital processing devices.

The standard will be an open system interface standard with emphasis towards direction finding, beamforming and phased array applications. The intended end-use is for both military and commercial systems.

The Data Streaming Packet structure will be defined to allow phase coherent signals from multiple sources to be delivered to multiple destinations such that signal phase may be maintained over multiple channels and digitized sample streams will maintain sample alignment over multiple channels.

The Status Packet will allow for non-signal data to be transferred from the tuner, such as channel identification, time-stamp, antennae orientation, tuning frequency, bandwidth and sample rate. A set of these typical communication parameters will be agreed upon and standardized.

Additionally, a system exclusive capability for conveying non-signal data will be provided for allowing application or manufacturer-specific data to be exchanged.

The packet structure will be link agnostic. It will be assumed that functions guaranteeing data link integrity (flow control, data error checking, etc) already exist and therefore are not part of the scope of this development. However, practical implications of the packet structure utilizing existing link technology will be considered.

As an option, the standard will also define "control messages" that can modify tuner/exciter behavior.

A cooperative effort with the Object Management Group (OMG) to define an application program interface (API) for the control messages will be investigated. As well, leveraging the use of extensible markup language (XML) for the control and status messages will be investigated.