1 Overview
Receive-side counterpart to ALF-RF-DUC. Each carrier has its own NCO, mixer and decimating filter chain, so a single wideband ADC stream can be split into independently tuned narrowband channels — the usual arrangement for multi-band receivers and for monitoring receivers that must watch several carriers at once.
2 Features
- Up to 16 independently tuned carriers from one input stream
- Decimation factors 2 – 4 096 with per-carrier settings
- Per-carrier NCO with 48-bit frequency resolution
- Independent digital gain and headroom control per carrier
- Overflow and saturation reporting at every stage
- Real-time carrier retuning with phase-continuous option
3 Applications
- O-RAN radio units and small cells
- Wideband transmit and receive signal chains
- Multi-carrier and multi-band radios
- Spectrum monitoring and surveillance receivers
4 Specifications
Figures below are for a representative configuration. Resource, latency and throughput scale with the build-time parameters; the released datasheet gives each as a closed-form function of those parameters so you can compute the number for your own configuration.
| Input rate | Up to 491.52 MSPS per stream |
|---|---|
| Carriers | 1 – 16 per instance |
| Decimation | 2 – 4 096, independent per carrier |
| Tuning resolution | 48-bit NCO, < 2 mHz at 491.52 MSPS |
| Alias rejection | Configurable, typically 80 – 100 dB |
| Interfaces | AXI4-Stream data, AXI4-Lite control |
| Typical FPGA | 8 kLUT, 72 DSP for 4 carriers @ 491.52 MHz |
| Product family | Digital Front-End |
| Availability | Production |
5 Interfaces and control
The core presents AXI4-Stream data, AXI4-Lite control. All streaming interfaces follow the AXI4-Stream handshake with full back-pressure support; the control plane is generated by ALF-CR-REGGEN, so the register map in section 5 is generated from the same source as the delivered VHDL and cannot drift from it.
The register map is delivered as an IP-XACT description alongside a C header and a UVM register abstraction layer, all generated together. Every field carries its access policy, reset value and any side effect in the generated documentation.
6 Configuration
The core is configured through a single package file of build-time parameters and an elaboration-time consistency check that fails the build — rather than failing in simulation — when a parameter combination is not supported. There is no source fork per configuration, so you stay on the mainline release and keep receiving maintenance updates.
Re-parameterisation within the documented range is covered by your licence at no additional cost. If you need a parameter outside the documented range, that is a design services conversation rather than a new licence.
7 Verification
ALF-RF-DDC is signed off against the release criteria described on the quality page: bit-exact agreement with the reference model across the regression suite, 100 % statement, branch and toggle coverage with every exclusion reviewed, formal proof of deadlock freedom and reset correctness on the control logic, and timing closure with positive slack on every supported target from the delivered constraints.
The verification environment used for that sign-off is part of the deliverable set. You can re-run it against your own configuration on your own farm.
8 Deliverables
| VHDL source | Synthesisable VHDL-2008, readable and commented, lint-clean |
|---|---|
| Closed-box alternative | Encrypted netlist or protected model, where source is not licensed |
| Reference model | Bit-accurate C++ (Python bindings) or MATLAB, with stimulus scripts |
| Verification | UVM testbench, functional coverage model, interface assertions |
| Test vectors | Directed and constrained-random sets with expected outputs |
| Synthesis | Timing constraints, build scripts and reference reports per target |
| Example design | Buildable project instantiating the core in a system context |
| Documentation | Datasheet, integration guide, register map, interface timing |
| Software | Bare-metal C driver and Linux reference driver, where applicable |
9 Licensing and ordering
ALF-RF-DDC is available under single-project, multi-project, evaluation and academic licences. All models are one-time fees with no per-unit royalty. See licensing for the full terms, or request a quotation quoting this part number.
10 Document revision history
| Revision | Date | Change |
|---|---|---|
| 0.1 | July 2026 | Initial preliminary draft |