Frontier offers GSM core written in C

Frontier offers GSM core written in C
By Peter Clarke, EE Times
April 27, 1999 (4:08 p.m. EST)
URL: http://www.eetimes.com/story/OEG19990427S0025

SANTA CLARA, Calif. — Frontier Design BV (Leuven, Belgium) has altered the world of intellectual property by offering a next-generation GSM baseband core written in the C language with a migration path to an ASIC or FPGA.

Designers will be able to use the C-language IP running on a digital-signal processor to prototype and debug a design, then move to a more cost-effective, lower-power hardware solution, Frontier said Monday (April 26) at the DSP World exhibition and conference here. The migration can be done using Frontier's Algorithm-to-Register-Transfer (A/RT) Builder EDA tool, which translates C to VHDL or Verilog before synthesis into hardware.

"This is the first time we've sold a complex core as C-language IP," said Herman Beke, Frontier's chief executive.

When this GSM Layer 1 system-level IP core is executed on a TMS320C62XX DSP from Texas Instruments Inc., it is capable of real-time processing for up to eight time slots, as ne eded for base stations but also sufficient for 384-kbit/second data-transmission rates for mobile phones that support emerging additions to the GSM standard for wireless Internet access.

"Today's commercially available GSM chip sets are limited to handsets and can process only a single time slot per processor, limiting them to a maximum data-transmission rate of 14.4 kbits/s," said Beke. "That's sufficient for voice or text but woefully inadequate for multimedia Internet access."

The European Telecommunications Standards Institute has created standards that raise GSM data rates over the present 9.6 or 14.4 kbits/s. These include general-packet radio service; high-speed circuit-switch data, which allocates up to eight time slots to a single user; and Edge, which increases the data that can fit into a single time slot from 14.4 to 64 kbits/s.

Higher rates

The combination of those three specs should enable wireless transmission rates of up to 384 kbits/s — nearly seven times f aster than a typical 56-kbit/s modem.

"Implementing these new standards is going to require throughput that vastly exceeds that available in today's GSM handset chip sets or DSP vendor-supplied assembly-language GSM code," said Beke."The GSM IP core we are introducing can provide the throughput required to support these high data-transmission rates today."

Beke also sees non-voice applications for the baseband core. "We believe there is a big market coming aimed not at GSM in the traditional way. [Instead] they could make use of a subset of the features," he said. "This is also aimed at small, innovative companies working on new ways to make use of GSM wireless data in areas like automotive systems or vending machines."

To that end the core has been divided into nine subcores, available individually or licensable all together. The subcores perform signal modulation, demodulation and equalization, data and voice encoding and decoding, speech synthesis and GSM full-rate and enhanced full-rate spee ch codecs.

The C core can be used in either Microsoft's Visual C++ development environment or compiled and run on a TMS320C62XX DSP chip. Either environment can be used for evaluation and system prototyping, but the TI implementation is targeted at real-time processing of up to eight time slots per device. The evaluation environments have test vectors and RF propagation models that can be used to verify performance against GSM specs.

Dave Coons, vice president of engineering at Frontier, explained that Level 1 functions cover all the features of baseband processing. Layer 2, excluded from the current Frontier core, covers maintenance of call integrity, while Layer 3 functions cover call setup and tear down, handover between cells and RF resource management.

The GSM core and subcores are provided in conjunction with design services, although customers may also license the core and use it without involving Frontier further. Licenses for the Microsoft Visual environment start at $650,000 and subcor es start at $50,000.

Beke said the licenses for the C-language cores are free of royalties, although development of chip implementations from the C language would be subject to negotiation. "Customers are allowed to develop chips from it but they cannot sublicense the original code," he said.