diff --git a/CMakeLists.txt b/CMakeLists.txt
index ccb689a..66fb76a 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -28,6 +28,7 @@ add_executable(blah2
   ${PROJECT_SOURCE_DIR}/process/detection/Centroid.cpp
   ${PROJECT_SOURCE_DIR}/process/detection/Interpolate.cpp
   ${PROJECT_SOURCE_DIR}/process/spectrum/SpectrumAnalyser.cpp
+  ${PROJECT_SOURCE_DIR}/process/meta/HammingNumber.cpp
   ${PROJECT_SOURCE_DIR}/data/IqData.cpp
   ${PROJECT_SOURCE_DIR}/data/Map.cpp
   ${PROJECT_SOURCE_DIR}/data/Detection.cpp
@@ -74,6 +75,7 @@ include_directories("${PROJECT_SOURCE_DIR}/process/ambiguity/")
 include_directories("${PROJECT_SOURCE_DIR}/process/clutter/")
 include_directories("${PROJECT_SOURCE_DIR}/process/detection/")
 include_directories("${PROJECT_SOURCE_DIR}/process/spectrum/")
+include_directories("${PROJECT_SOURCE_DIR}/process/meta/")
 include_directories("${PROJECT_SOURCE_DIR}/data/")
 include_directories("${PROJECT_SOURCE_DIR}/data/meta/")
 
@@ -82,6 +84,7 @@ add_executable(testAmbiguity
   ${PROJECT_TEST_DIR}/unit/process/ambiguity/TestAmbiguity.cpp
   ${PROJECT_SOURCE_DIR}/data/IqData.cpp
   ${PROJECT_SOURCE_DIR}/data/Map.cpp
-  ${PROJECT_SOURCE_DIR}/process/ambiguity/Ambiguity.cpp)
+  ${PROJECT_SOURCE_DIR}/process/ambiguity/Ambiguity.cpp
+  ${PROJECT_SOURCE_DIR}/process/meta/HammingNumber.cpp)
 target_link_libraries(testAmbiguity catch2 fftw3 fftw3_threads)
 set_target_properties(testAmbiguity PROPERTIES RUNTIME_OUTPUT_DIRECTORY "${PROJECT_BINARY_TEST_DIR}")
diff --git a/src/process/ambiguity/Ambiguity.cpp b/src/process/ambiguity/Ambiguity.cpp
index 05ddf3e..6a3d683 100644
--- a/src/process/ambiguity/Ambiguity.cpp
+++ b/src/process/ambiguity/Ambiguity.cpp
@@ -183,45 +183,6 @@ Map<std::complex<double>> *Ambiguity::process(IqData *x, IqData *y)
   return map_.get();
 }
 
-/**
- * @brief Hamming number generator
- *
- * @author Nigel Galloway
- * @cite https://rosettacode.org/wiki/Hamming_numbers
- * @todo Can this be done with constexpr???
- */
-class HammingGenerator {
-private:
-	std::vector<unsigned int> _H, _hp, _hv, _x;
-public:
-  bool operator!=(const HammingGenerator &other) const { return true; }
-  HammingGenerator begin() const { return *this; }
-  HammingGenerator end() const { return *this; }
-  unsigned int operator*() const { return _x.back(); }
-  HammingGenerator(const std::vector<unsigned int> &pfs) : _H(pfs), _hp(pfs.size(), 0), _hv({pfs}), _x({1}) {}
-  const HammingGenerator &operator++()
-  {
-    for (int i = 0; i < _H.size(); i++)
-      for (; _hv[i] <= _x.back(); _hv[i] = _x[++_hp[i]] * _H[i])
-        ;
-    _x.push_back(_hv[0]);
-    for (int i = 1; i < _H.size(); i++)
-      if (_hv[i] < _x.back())
-        _x.back() = _hv[i];
-    return *this;
-  }
-};
-
-
-uint32_t next_hamming(uint32_t value) {
-  for (auto i : HammingGenerator({2,3,5})) {
-    if (i > value) {
-      return i;
-    }
-  }
-  return 0;
-}
-
 std::ostream& operator<<(std::ostream& str, const Ambiguity::PerformanceStats& stats) {
   return str << "Total time: " << stats.process_time_ms << "ms\n" <<
                 "Range FFT time: " << stats.range_fft_time_ms << "ms\n" <<
diff --git a/src/process/ambiguity/Ambiguity.h b/src/process/ambiguity/Ambiguity.h
index 5c0dc06..5d93094 100644
--- a/src/process/ambiguity/Ambiguity.h
+++ b/src/process/ambiguity/Ambiguity.h
@@ -10,6 +10,7 @@
 
 #include <IqData.h>
 #include <Map.h>
+#include <HammingNumber.h>
 #include <stdint.h>
 #include <fftw3.h>
 #include <memory>
@@ -126,9 +127,4 @@ private:
   PerformanceStats latest_performance_;
 };
 
-/// @brief  Calculate the next 5-smooth Hamming Number larger than value
-/// @param value Value to round
-/// @return value rounded to Hamming number
-uint32_t next_hamming(uint32_t value);
-
 std::ostream& operator<<(std::ostream& str, const Ambiguity::PerformanceStats& stats);
\ No newline at end of file
diff --git a/src/process/meta/HammingNumber.cpp b/src/process/meta/HammingNumber.cpp
new file mode 100644
index 0000000..5621159
--- /dev/null
+++ b/src/process/meta/HammingNumber.cpp
@@ -0,0 +1,40 @@
+#include "HammingNumber.h"
+
+bool HammingNumber::operator!=(const HammingNumber &other) const {
+    return true;
+}
+
+HammingNumber HammingNumber::begin() const {
+    return *this;
+}
+
+HammingNumber HammingNumber::end() const {
+    return *this;
+}
+
+unsigned int HammingNumber::operator*() const {
+    return _x.back();
+}
+
+HammingNumber::HammingNumber(const std::vector<unsigned int> &pfs)
+    : _H(pfs), _hp(pfs.size(), 0), _hv({pfs}), _x({1}) {}
+
+const HammingNumber &HammingNumber::operator++() {
+    for (int i = 0; i < _H.size(); i++)
+        for (; _hv[i] <= _x.back(); _hv[i] = _x[++_hp[i]] * _H[i])
+            ;
+    _x.push_back(_hv[0]);
+    for (int i = 1; i < _H.size(); i++)
+        if (_hv[i] < _x.back())
+            _x.back() = _hv[i];
+    return *this;
+}
+
+uint32_t next_hamming(uint32_t value) {
+    for (auto i : HammingNumber({2, 3, 5})) {
+        if (i > value) {
+            return i;
+        }
+    }
+    return 0;
+}
diff --git a/src/process/meta/HammingNumber.h b/src/process/meta/HammingNumber.h
new file mode 100644
index 0000000..9f511ac
--- /dev/null
+++ b/src/process/meta/HammingNumber.h
@@ -0,0 +1,34 @@
+/// @file HammingNumber.h
+/// @class HammingNumber
+/// @brief Hamming number generator
+/// @author Nigel Galloway
+/// @cite https://rosettacode.org/wiki/Hamming_numbers
+/// @todo Can this be done with constexpr???
+
+#ifndef HAMMING_GENERATOR_H
+#define HAMMING_GENERATOR_H
+
+#include <vector>
+#include <stdint.h>
+
+class HammingNumber 
+{
+
+  private:
+      std::vector<unsigned int> _H, _hp, _hv, _x;
+
+  public:
+      bool operator!=(const HammingNumber &other) const;
+      HammingNumber begin() const;
+      HammingNumber end() const;
+      unsigned int operator*() const;
+      HammingNumber(const std::vector<unsigned int> &pfs);
+      const HammingNumber &operator++();
+};
+
+/// @brief  Calculate the next 5-smooth Hamming Number larger than value
+/// @param value Value to round
+/// @return value rounded to Hamming number
+uint32_t next_hamming(uint32_t value);
+
+#endif
\ No newline at end of file
diff --git a/src/process/spectrum/SpectrumAnalyser.h b/src/process/spectrum/SpectrumAnalyser.h
index 7140cca..7057500 100644
--- a/src/process/spectrum/SpectrumAnalyser.h
+++ b/src/process/spectrum/SpectrumAnalyser.h
@@ -4,6 +4,7 @@
 /// @details Simple decimate and FFT on CPI IQ data for frequency spectrum.
 /// @author 30hours
 /// @todo Potentially create k spectrum plots from sub-CPIs.
+/// @todo FFT with HammingNumber class.
 
 #ifndef SPECTRUMANALYSER_H
 #define SPECTRUMANALYSER_H