phy: remove resource grid coordinate put

Author: xavierarteaga

include/srsran/phy/support/resource_grid_writer.h

@@ -17,34 +17,6 @@
 
 namespace srsran {
 
-/// Describes a resource grid coordinate as symbol index and carrier.
-struct resource_grid_coordinate {
-  /// Symbol index (0...13).
-  uint8_t symbol = 0;
-  /// Subcarrier index (0...3299).
-  uint16_t subcarrier = 0;
-
-  /// Default destructor
-  resource_grid_coordinate() = default;
-
-  /// \brief Constructor from \c unsigned values.
-  /// \param[in] symbol_     Provides the \c symbol value.
-  /// \param[in] subcarrier_ Provides the \c subcarrier value.
-  resource_grid_coordinate(unsigned symbol_, unsigned subcarrier_) :
-    symbol(static_cast<uint8_t>(symbol_)), subcarrier(static_cast<uint16_t>(subcarrier_))
-  {
-  }
-
-  /// \brief Overloads equal comparison operator.
-  ///
-  /// Two resource grid coordinates are equal when symbol and subcarrier indexes are equal.
-  /// \param[in] other The comparing coordinate.
-  bool operator==(const resource_grid_coordinate& other) const
-  {
-    return (other.symbol == symbol) && (subcarrier == other.subcarrier);
-  }
-};
-
 /// \brief Resource grid writer interface.
 ///
 /// Contains the necessary functions to write resource elements in a resource grid.
@@ -56,14 +28,6 @@ class resource_grid_writer : public resource_grid_base
   /// Default destructor
   virtual ~resource_grid_writer() = default;
 
-  /// \brief Puts a number of elements in the grid for a given port according to a list of coordinates.
-  ///
-  /// \param[in] port        Port index.
-  /// \param[in] coordinates List of grid symbol&ndash;subcarrier coordinates.
-  /// \param[in] symbols     List of symbols to written at the specified coordinates.
-  /// \note The number of elements in \c coordinates and \c symbols shall be the same.
-  virtual void put(unsigned port, span<const resource_grid_coordinate> coordinates, span<const cf_t> symbols) = 0;
-
   /// \brief Puts a number of resource elements in the resource grid at the given port and symbol using a mask to
   /// indicate which subcarriers are allocated and which are not.
   ///

lib/phy/support/resource_grid_writer_impl.cpp

@@ -29,37 +29,6 @@ unsigned resource_grid_writer_impl::get_nof_symbols() const
   return data.get_dimension_size(resource_grid_dimensions::symbol);
 }
 
-void resource_grid_writer_impl::put(unsigned                             port,
-                                    span<const resource_grid_coordinate> coordinates,
-                                    span<const cf_t>                     symbols)
-{
-  srsran_assert(coordinates.size() == symbols.size(),
-                "The number of coordinates {} is not equal to the number of symbols {}.",
-                coordinates.size(),
-                symbols.size());
-
-  srsran_assert(port < get_nof_ports(), "The port index {} is out of range (max {}).", port, get_nof_ports() - 1);
-
-  unsigned count = 0;
-  for (const resource_grid_coordinate& coordinate : coordinates) {
-    srsran_assert(coordinate.symbol < get_nof_symbols(),
-                  "Symbol index {} is out of range (max {}).",
-                  coordinate.symbol,
-                  get_nof_symbols());
-    srsran_assert(coordinate.subcarrier < get_nof_subc(),
-                  "Subcarrier index {} is out of range (max {}).",
-                  coordinate.subcarrier,
-                  get_nof_subc());
-
-    // Select destination OFDM symbol from the resource grid.
-    span<cf_t> rg_symbol = data.get_view({coordinate.symbol, port});
-
-    // Write into the desired resource element.
-    rg_symbol[coordinate.subcarrier] = symbols[count++];
-  }
-  clear_empty(port);
-}
-
 span<const cf_t> resource_grid_writer_impl::put(unsigned         port,
                                                 unsigned         l,
                                                 unsigned         k_init,

lib/phy/support/resource_grid_writer_impl.h

@@ -32,9 +32,6 @@ class resource_grid_writer_impl : public resource_grid_writer
   // See interface for documentation.
   unsigned get_nof_symbols() const override;
 
-  // See interface for documentation.
-  void put(unsigned port, span<const resource_grid_coordinate> coordinates, span<const cf_t> symbols) override;
-
   // See interface for documentation.
   span<const cf_t>
   put(unsigned port, unsigned l, unsigned k_init, span<const bool> mask, span<const cf_t> symbols) override;

lib/phy/upper/channel_processors/pbch_modulator_impl.cpp

@@ -39,48 +39,42 @@ void pbch_modulator_impl::modulate(span<const uint8_t> b_hat, span<cf_t> d_pbch)
 
 void pbch_modulator_impl::map(span<const cf_t> d_pbch, resource_grid_writer& grid, const config_t& config)
 {
-  unsigned count = 0;
-  unsigned l0    = config.ssb_first_symbol;
-  unsigned k0    = config.ssb_first_subcarrier;
+  unsigned l0 = config.ssb_first_symbol;
+  unsigned k0 = config.ssb_first_subcarrier;
 
-  // Calculate DMRS index shift
+  // Calculate DM-RS index shift.
   uint32_t v = config.phys_cell_id % 4;
 
-  // Create resource grid coordinates
-  std::array<resource_grid_coordinate, M_symb> coordinates;
+  // Resource element mask within each resource block. Remove DM-RS from the mask.
+  bounded_bitset<NRE> re_mask = ~bounded_bitset<NRE>(NRE);
+  re_mask.reset(v);
+  re_mask.reset(v + 4);
+  re_mask.reset(v + 8);
 
-  // Put sequence in symbol 1 (0, 1, ..., 239) not reserved for PBCH DM-RS
-  for (uint32_t k = 0; k < SSB_BW_RE; ++k) {
-    if (k % 4 != v) {
-      coordinates[count++] = {l0 + 1, k0 + k};
-    }
-  }
+  // Full SS/PBCH block bandwidth resource blocks.
+  bounded_bitset<MAX_RB>      rb_full_mask = ~bounded_bitset<MAX_RB>(SSB_BW_RB);
+  bounded_bitset<NRE* MAX_RB> full_mask    = rb_full_mask.kronecker_product<NRE>(re_mask);
 
-  // Put sequence in symbol 2, lower section (0 + v , 4 + v , 8 + v ,..., 44 + v) not reserved for PBCH DM-RS
-  for (uint32_t k = 0; k < 48; ++k) {
-    if (k % 4 != v) {
-      coordinates[count++] = {l0 + 2, k0 + k};
-    }
-  }
+  // Edges SS/PBCH block bandwidth resource blocks.
+  bounded_bitset<MAX_RB> rb_edge_mask = bounded_bitset<MAX_RB>(SSB_BW_RB);
+  rb_edge_mask.fill(0, 4);
+  rb_edge_mask.fill(16, 20);
+  bounded_bitset<NRE* MAX_RB> edge_mask = rb_edge_mask.kronecker_product<NRE>(re_mask);
 
-  // Put sequence in symbol 2, upper section (192 + v , 196 + v ,..., 236 + v) not reserved for PBCH DM-RS
-  for (uint32_t k = 192; k < SSB_BW_RE; ++k) {
-    if (k % 4 != v) {
-      coordinates[count++] = {l0 + 2, k0 + k};
-    }
-  }
+  // Map symbols for each of the ports.
+  for (unsigned port : config.ports) {
+    span<const cf_t> symbols = d_pbch;
 
-  // Put sequence in symbol 3 (0, 1, ..., 239) not reserved for PBCH DM-RS
-  for (uint32_t k = 0; k < SSB_BW_RE; ++k) {
-    if (k % 4 != v) {
-      coordinates[count++] = {l0 + 3, k0 + k};
-    }
-  }
+    // Put sequence in symbol 1 (0, 1, ..., 239), skip the subcarriers reserved for PBCH DM-RS.
+    symbols = grid.put(port, l0 + 1, k0, full_mask, symbols);
 
-  // For each port
-  for (unsigned port : config.ports) {
-    // write data in grid
-    grid.put(port, coordinates, d_pbch);
+    // Put sequence in symbol 2 (0, 1, ..., 41) and (192, 193, ..., 239), skip the subcarriers reserved for PBCH DM-RS.
+    symbols = grid.put(port, l0 + 2, k0, edge_mask, symbols);
+
+    // Put sequence in symbol 3 (0, 1, ..., 239), skip the subcarriers reserved for PBCH DM-RS.
+    symbols = grid.put(port, l0 + 3, k0, full_mask, symbols);
+
+    srsran_assert(symbols.empty(), "Symbols must be empty.");
   }
 }
 

lib/phy/upper/signal_processors/dmrs_pbch_processor_impl.cpp

@@ -40,42 +40,31 @@ void dmrs_pbch_processor_impl::mapping(const std::array<cf_t, NOF_RE>& r,
                                        resource_grid_writer&           grid,
                                        const config_t&                 args) const
 {
-  // Calculate index shift
+  // Calculate index shift.
   uint32_t v = args.phys_cell_id % 4;
 
-  // r sequence read index
-  uint32_t r_idx = 0;
-
-  // Create resource grid coordinates
-  std::array<resource_grid_coordinate, NOF_RE> coordinates;
-
   const uint8_t  l0 = args.ssb_first_symbol;
   const uint16_t k0 = args.ssb_first_subcarrier;
 
-  // Put sequence in symbol 1 (0 + v , 4 + v , 8 + v ,..., 236 + v)
-  for (uint16_t k = v; k < SSB_BW_RE; k += 4) {
-    coordinates[r_idx++] = resource_grid_coordinate(l0 + 1, k0 + k);
-  }
+  // For each port...
+  for (unsigned port : args.ports) {
+    // Create view with the symbols.
+    span<const cf_t> symbols = r;
 
-  // Put sequence in symbol 2, lower section (0 + v , 4 + v , 8 + v ,..., 44 + v)
-  for (uint16_t k = v; k < 48; k += 4) {
-    coordinates[r_idx++] = resource_grid_coordinate(l0 + 2, k0 + k);
-  }
+    // Put sequence in symbol 1 (0 + v , 4 + v , 8 + v ,..., 236 + v).
+    grid.put(port, l0 + 1, k0 + v, stride, symbols.first(nof_dmrs_full_symbol));
+    symbols = symbols.last(symbols.size() - nof_dmrs_full_symbol);
 
-  // Put sequence in symbol 2, upper section
-  for (uint32_t k = 192 + v; k < SSB_BW_RE; k += 4) {
-    coordinates[r_idx++] = resource_grid_coordinate(l0 + 2, k0 + k);
-  }
+    // Put sequence in symbol 2, lower section (0 + v , 4 + v , 8 + v ,..., 44 + v).
+    grid.put(port, l0 + 2, k0 + v, stride, symbols.first(nof_dmrs_edge_symbol));
+    symbols = symbols.last(symbols.size() - nof_dmrs_edge_symbol);
 
-  // Put sequence in symbol 3
-  for (uint32_t k = v; k < SSB_BW_RE; k += 4) {
-    coordinates[r_idx++] = resource_grid_coordinate(l0 + 3, k0 + k);
-  }
+    // Put sequence in symbol 2, upper section (192 + v , 196 + v , 200 + v ,..., 236 + v).
+    grid.put(port, l0 + 2, k0 + v + 192, stride, symbols.first(nof_dmrs_edge_symbol));
+    symbols = symbols.last(symbols.size() - nof_dmrs_edge_symbol);
 
-  // For each port...
-  for (unsigned port : args.ports) {
-    // ... put data in grid using the generated coordinates
-    grid.put(port, coordinates, r);
+    // Put sequence in symbol 3 (0 + v , 4 + v , 8 + v ,..., 236 + v).
+    grid.put(port, l0 + 3, k0 + v, stride, symbols.first(nof_dmrs_full_symbol));
   }
 }
 

lib/phy/upper/signal_processors/dmrs_pbch_processor_impl.h

@@ -20,8 +20,16 @@ namespace srsran {
 class dmrs_pbch_processor_impl : public dmrs_pbch_processor
 {
 private:
-  /// DMRS PBCH Sequence length in the SSB
-  static const unsigned NOF_RE = 144;
+  /// PBCH DM-RS stride within a resource block.
+  static constexpr unsigned stride = 4U;
+  /// Number of PBCH DM-RS per resource block.
+  static constexpr unsigned nof_dmrs_prb = NRE / stride;
+  /// Number of PBCH DM-RS contained in a full SS/PBCH block OFDM symbol.
+  static constexpr unsigned nof_dmrs_full_symbol = SSB_BW_RB * nof_dmrs_prb;
+  /// Number of PBCH DM-RS contained in one edge SS/PBCH block OFDM symbol.
+  static constexpr unsigned nof_dmrs_edge_symbol = 4 * nof_dmrs_prb;
+  /// Total number of resource elements for PBCH DM-RS in a SS/PBCH block.
+  static constexpr unsigned NOF_RE = 2 * nof_dmrs_full_symbol + 2 * nof_dmrs_edge_symbol;
 
   std::unique_ptr<pseudo_random_generator> prg;
 

tests/unittests/ofh/receiver/helpers.h

@@ -69,11 +69,6 @@ class resource_grid_writer_bool_spy : public resource_grid_writer
   unsigned get_nof_ports() const override { return 1; };
   unsigned get_nof_subc() const override { return 51 * NOF_SUBCARRIERS_PER_RB; };
   unsigned get_nof_symbols() const override { return MAX_NSYMB_PER_SLOT; };
-  void     put(unsigned port, span<const resource_grid_coordinate> coordinates, span<const cf_t> symbols) override
-  {
-    grid_written = true;
-    nof_prbs_written += symbols.size() / NOF_SUBCARRIERS_PER_RB;
-  }
 
   span<const cf_t>
   put(unsigned port, unsigned l, unsigned k_init, span<const bool> mask, span<const cf_t> symbols) override

tests/unittests/ofh/transmitter/ofh_uplink_request_handler_impl_test.cpp

@@ -96,7 +96,6 @@ class resource_grid_dummy : public resource_grid
     unsigned get_nof_ports() const override { return 1; }
     unsigned get_nof_subc() const override { return 1; }
     unsigned get_nof_symbols() const override { return 1; }
-    void     put(unsigned port, span<const resource_grid_coordinate> coordinates, span<const cf_t> symbols) override {}
     span<const cf_t>
     put(unsigned port, unsigned l, unsigned k_init, span<const bool> mask, span<const cf_t> symbols) override
     {

tests/unittests/phy/support/resource_grid_test.cpp

@@ -58,73 +58,6 @@ void test_all_zero(unsigned nof_ports, unsigned nof_symbols, unsigned nof_subc)
   }
 }
 
-void test_coordinates(unsigned nof_ports, unsigned nof_symbols, unsigned nof_subc, unsigned nof_elements)
-{
-  // Create grid and zero
-  std::unique_ptr<resource_grid> grid = create_resource_grid(nof_ports, nof_symbols, nof_subc);
-  grid->set_all_zero();
-
-  // Random distributions
-  std::uniform_int_distribution<unsigned> port_dist(0, nof_ports - 1);
-  std::uniform_int_distribution<uint8_t>  symbol_dist(0, nof_symbols - 1);
-  std::uniform_int_distribution<uint16_t> subc_dist(0, nof_subc - 1);
-  std::uniform_real_distribution<float>   value_dist(-1.0, +1.0);
-
-  std::vector<resource_grid_coordinate> coordinates(nof_elements);
-  std::vector<cf_t>                     symbols_gold(nof_elements);
-
-  // Generate random elements
-  unsigned port_gold = port_dist(rgen);
-  for (unsigned i = 0; i != nof_elements; ++i) {
-    // Generate coordinate, making sure there are no double entries
-    bool doubled;
-    do {
-      doubled        = false;
-      coordinates[i] = {symbol_dist(rgen), subc_dist(rgen)};
-
-      // Check if the coordinate exists
-      for (unsigned j = 0; j != i && !doubled; ++j) {
-        doubled = (coordinates[i] == coordinates[j]);
-      }
-    } while (doubled);
-
-    // Create random value
-    symbols_gold[i] = {value_dist(rgen), value_dist(rgen)};
-  }
-
-  // Put elements in resource grid
-  grid->get_writer().put(port_gold, coordinates, symbols_gold);
-
-  // Assert grid
-  for (unsigned port = 0; port != nof_ports; ++port) {
-    // Verify the grid for the port is NOT empty.
-    TESTASSERT_EQ(port != port_gold, grid->get_reader().is_empty(port));
-
-    for (unsigned symbol = 0; symbol != nof_symbols; ++symbol) {
-      // Get resource grid data for the given symbol
-      std::vector<cf_t> rg_data(nof_subc);
-      grid->get_reader().get(rg_data, port, symbol, 0);
-
-      for (unsigned subc = 0; subc != nof_subc; ++subc) {
-        cf_t gold  = {0.0, 0.0};
-        cf_t value = rg_data[subc];
-
-        // Try to find the RE in coordinates
-        resource_grid_coordinate coordinate = {symbol, subc};
-        for (unsigned i = 0; i != nof_elements; ++i) {
-          if (port == port_gold && coordinates[i] == coordinate) {
-            gold = symbols_gold[i];
-            break;
-          }
-        }
-
-        TESTASSERT_EQ(gold.real(), value.real());
-        TESTASSERT_EQ(gold.imag(), value.imag());
-      }
-    }
-  }
-}
-
 void test_mask(unsigned nof_ports, unsigned nof_symbols, unsigned nof_subc, unsigned nof_elements)
 {
   // Create grid and zero
@@ -378,7 +311,6 @@ int main()
         test_all_zero(nof_ports, nof_symbols, nof_subc);
         // Test symbolic number of elements
         for (unsigned nof_elements : {1, 2, 4, 8, 16, 32}) {
-          test_coordinates(nof_ports, nof_symbols, nof_subc, nof_elements);
           test_mask(nof_ports, nof_symbols, nof_subc, nof_elements);
           test_mask_bitset(nof_ports, nof_symbols, nof_subc, nof_elements);
           test_consecutive(nof_ports, nof_symbols, nof_subc, nof_elements);

tests/unittests/phy/support/resource_grid_test_doubles.h

@@ -68,18 +68,6 @@ class resource_grid_writer_spy : public resource_grid_writer
   // See interface for documentation.
   unsigned get_nof_symbols() const override { return max_symb; }
 
-  // See interface for documentation.
-  void put(unsigned port, span<const resource_grid_coordinate> coordinates, span<const cf_t> symbols) override
-  {
-    std::unique_lock<std::mutex> lock(entries_mutex);
-    ++count;
-    const cf_t* symbol_ptr = symbols.begin();
-    for (const resource_grid_coordinate& coordinate : coordinates) {
-      put(port, coordinate.symbol, coordinate.subcarrier, *(symbol_ptr++));
-    }
-    fmt::print("entries.size()={}\n", entries.size());
-  }
-
   // See interface for documentation.
   span<const cf_t>
   put(unsigned port, unsigned l, unsigned k_init, span<const bool> mask, span<const cf_t> symbols) override