new SINR threshold comms CBF constraint

@agent/agent.m

@@ -19,7 +19,8 @@ classdef agent
         fovGeometry;
 
         % Communication
-        commsGeometry;
+        commsGeometry;          % fixed-radius comms model (spherical, radius = comRange)
+        txPower = 0.1;          % transmit power (W) for the SINR comms model (isotropic)
         lesserNeighbors = zeros(1, 0);
 
         % Performance
@@ -49,7 +50,7 @@ classdef agent
             obj.fovGeometry = cone;
             obj.commsGeometry = spherical;
         end
-        [obj] = initialize(obj, pos, pan, tilt, collisionGeometry, sensorModel, guidanceModel, comRange, index, label);
+        [obj] = initialize(obj, pos, collisionGeometry, sensorModel, comRange, maxIter, initialStepSize, initialMaxAngleStepSize, label, plotCommsGeometry, txPower);
         [obj] = run(obj, domain, partitioning, t, index, useDoubleIntegrator, dampingCoeff, dt, optimizeSensorPointing, otherAgents);
         [partitioning, agents] = partition(obj, agents, objective)
         [obj, f] = plot(obj, ind, f);

@agent/initialize.m

@@ -1,4 +1,4 @@
-function obj = initialize(obj, pos, collisionGeometry, sensorModel, comRange, maxIter, initialStepSize, initialMaxAngleStepSize, label, plotCommsGeometry)
+function obj = initialize(obj, pos, collisionGeometry, sensorModel, comRange, maxIter, initialStepSize, initialMaxAngleStepSize, label, plotCommsGeometry, txPower)
     arguments (Input)
         obj (1, 1) {mustBeA(obj, "agent")};
         pos (1, 3) double;
@@ -10,6 +10,7 @@ function obj = initialize(obj, pos, collisionGeometry, sensorModel, comRange, ma
         initialMaxAngleStepSize (1, 1) double = 5.0;
         label (1, 1) string = "";
         plotCommsGeometry (1, 1) logical = false;
+        txPower (1, 1) double = 0.1;
     end
     arguments (Output)
         obj (1, 1) {mustBeA(obj, "agent")};
@@ -25,6 +26,7 @@ function obj = initialize(obj, pos, collisionGeometry, sensorModel, comRange, ma
     obj.plotCommsGeometry = plotCommsGeometry;
     obj.initialStepSize = initialStepSize;
     obj.initialMaxAngleStepSize = initialMaxAngleStepSize;
+    obj.txPower = txPower;
     obj.stepDecayRate = obj.initialStepSize / maxIter;
     obj.angleStepDecayRate = obj.initialMaxAngleStepSize / maxIter;
 

@miSim/constrainMotion.m

@@ -141,31 +141,72 @@ function [obj] = constrainMotion(obj)
     % Add communication network constraints
     hComms = NaN(nAgents, nAgents);
     hComms(logical(eye(nAgents))) = 0;
-    for ii = 1:(nAgents - 1)
+    if ~obj.useSinrComms
-        for jj = (ii + 1):nAgents
+        % Fixed-radius comms: keep each maintained pair within the smaller of
-            if obj.constraintAdjacencyMatrix(ii, jj)
+        % the two comms radii via the barrier h = r_comms^2 - dist^2.
-                paddingFactor = 0.9; % Barrier at 90% of actual range; real comms still work beyond this
+        for ii = 1:(nAgents - 1)
-                r_comms = paddingFactor * min([obj.agents{ii}.commsGeometry.radius, obj.agents{jj}.commsGeometry.radius]);
+            for jj = (ii + 1):nAgents
-                hComms(ii, jj) = r_comms^2 - norm(obj.agents{ii}.lastPos - obj.agents{jj}.lastPos)^2;
+                if obj.constraintAdjacencyMatrix(ii, jj)
+                    paddingFactor = 0.9; % Barrier at 90% of actual range; real comms still work beyond this
+                    r_comms = paddingFactor * min([obj.agents{ii}.commsGeometry.radius, obj.agents{jj}.commsGeometry.radius]);
+                    hComms(ii, jj) = r_comms^2 - norm(obj.agents{ii}.lastPos - obj.agents{jj}.lastPos)^2;
 
-                A(kk, (3 * ii - 2):(3 * ii)) =  2 * (obj.agents{ii}.lastPos - obj.agents{jj}.lastPos);
+                    A(kk, (3 * ii - 2):(3 * ii)) =  2 * (obj.agents{ii}.lastPos - obj.agents{jj}.lastPos);
-                A(kk, (3 * jj - 2):(3 * jj)) = -A(kk, (3 * ii - 2):(3 * ii));
+                    A(kk, (3 * jj - 2):(3 * jj)) = -A(kk, (3 * ii - 2):(3 * ii));
 
-                % One-step forward invariance: b = h/dt ensures h cannot
+                    % One-step forward invariance: b = h/dt ensures h cannot
-                % go negative in a single timestep (linear approximation)
+                    % go negative in a single timestep (linear approximation)
-                v_max_ij = max(obj.agents{ii}.initialStepSize, obj.agents{jj}.initialStepSize) / obj.timestep;
+                    v_max_ij = max(obj.agents{ii}.initialStepSize, obj.agents{jj}.initialStepSize) / obj.timestep;
-                hMin = -4 * r_comms * v_max_ij * obj.timestep;
+                    hMin = -4 * r_comms * v_max_ij * obj.timestep;
-                if norm(A(kk, :)) < 1e-9
+                    if norm(A(kk, :)) < 1e-9
-                    b(kk) = 0;
+                        b(kk) = 0;
-                else
+                    else
-                    b(kk) = max(hMin, hComms(ii, jj)) / obj.timestep;
+                        b(kk) = max(hMin, hComms(ii, jj)) / obj.timestep;
+                    end
+
+                    kk = kk + 1;
                 end
+            end
+        end
+    else
+        % SINR comms: keep the SINR of each maintained link above threshold via
+        % the barrier h = SINR - gammaLin. Per the connectivity convention the
+        % lower-index agent (ii) receives the higher-index transmitter (jj). The
+        % gradient couples the receiver, transmitter, and every interferer, so
+        % the QP row is dense across all agent blocks.
+        % Maintain SINR a margin above the connectivity threshold so that
+        % discrete-time overshoot of the (convex) SINR does not transiently
+        % drop a maintained link below threshold. Mirrors the fixed-radius
+        % barrier's 0.9 padding: the CBF holds SINR >= gammaCbf > gammaLin,
+        % while connectivity (updateAdjacency) still uses gammaLin.
+        paddingDb = 3.0;
+        gammaCbf = 10^((obj.sinrThreshold + paddingDb) / 10);
+        lastPositions = zeros(nAgents, 3);
+        for ll = 1:nAgents
+            lastPositions(ll, :) = obj.agents{ll}.lastPos;
+        end
+        for ii = 1:(nAgents - 1)
+            for jj = (ii + 1):nAgents
+                if obj.constraintAdjacencyMatrix(ii, jj)
+                    [sinr, grad] = obj.sinrLink(lastPositions, ii, jj); % receiver ii, transmitter jj
+                    hComms(ii, jj) = sinr - gammaCbf;
 
-                kk = kk + 1;
+                    % CBF row: A = -grad(h), b = h/dt (one-step forward invariance)
+                    for aa = 1:nAgents
+                        A(kk, (3 * aa - 2):(3 * aa)) = -grad(aa, :);
+                    end
+                    if norm(A(kk, :)) < 1e-9
+                        b(kk) = 0;
+                    else
+                        b(kk) = hComms(ii, jj) / obj.timestep;
+                    end
+
+                    kk = kk + 1;
+                end
             end
         end
     end
-    
+
     if coder.target('MATLAB')
 	obj.barriers(idx:(idx + length(hComms(triu(true(size(hComms)), 1))) - 1), obj.timestepIndex) = hComms(triu(true(size(hComms)), 1));
     end

@miSim/initialize.m

@@ -1,4 +1,4 @@
-function [obj] = initialize(obj, domain, agents, barrierGain, barrierExponent, minAlt, timestep, maxIter, obstacles, makePlots, makeVideo, useDoubleIntegrator, dampingCoeff, useFixedTopology, optimizeSensorPointing)
+function [obj] = initialize(obj, domain, agents, barrierGain, barrierExponent, minAlt, timestep, maxIter, obstacles, makePlots, makeVideo, useDoubleIntegrator, dampingCoeff, useFixedTopology, optimizeSensorPointing, useSinrComms, sinrThreshold, pathLossExponent, ambientTemp, centerFreq, bandwidth)
     arguments (Input)
         obj (1, 1) {mustBeA(obj, "miSim")};
         domain (1, 1) {mustBeGeometry};
@@ -15,6 +15,12 @@ function [obj] = initialize(obj, domain, agents, barrierGain, barrierExponent, m
         dampingCoeff (1, 1) double = 2.0;
         useFixedTopology (1, 1) logical = false;
         optimizeSensorPointing (1, 1) logical = false;
+        useSinrComms (1, 1) logical = false;
+        sinrThreshold (1, 1) double = 0;
+        pathLossExponent (1, 1) double = 2.0;
+        ambientTemp (1, 1) double = 290.0;
+        centerFreq (1, 1) double = 2.4e9;
+        bandwidth (1, 1) double = 20e6;
     end
     arguments (Output)
         obj (1, 1) {mustBeA(obj, "miSim")};
@@ -98,6 +104,14 @@ function [obj] = initialize(obj, domain, agents, barrierGain, barrierExponent, m
     obj.useFixedTopology = useFixedTopology;
     obj.optimizeSensorPointing = optimizeSensorPointing;
 
+    % Set communications model and SINR parameters
+    obj.useSinrComms = useSinrComms;
+    obj.sinrThreshold = sinrThreshold;
+    obj.pathLossExponent = pathLossExponent;
+    obj.ambientTemp = ambientTemp;
+    obj.centerFreq = centerFreq;
+    obj.bandwidth = bandwidth;
+
     % Compute adjacency matrix and network topology
     obj = obj.updateAdjacency();
     if obj.useFixedTopology
@@ -126,7 +140,11 @@ function [obj] = initialize(obj, domain, agents, barrierGain, barrierExponent, m
     end
     nAOPairs = size(obj.agents, 1) * size(obj.obstacles, 1); % unique agent/obstacle pairs
     nADPairs = size(obj.agents, 1) * 6; % agents x (4 walls + 1 floor + 1 ceiling)
-    nLNAPairs = sum(triu(obj.constraintAdjacencyMatrix, 1), "all");
+    % Comms barriers: size to the upper bound (full mesh) rather than the initial
+    % constraint-adjacency count. Connectivity is dynamic (lesser-neighbor and,
+    % especially, SINR) and can later maintain more pairs than at init; sizing to
+    % nAAPairs prevents the QP A/b matrices from overflowing mid-run.
+    nLNAPairs = nAAPairs;
     obj.numBarriers = nAAPairs + nAOPairs + nADPairs + nLNAPairs;
 
     if coder.target('MATLAB')

@miSim/initializeFromCsv.m

@@ -107,6 +107,46 @@ else
     USE_FIXED_TOPOLOGY = false;
 end
 
+% SINR communications model (optional columns — backward compatible with
+% older CSVs that predate the SINR model; defaults keep the fixed-radius path)
+if isfield(scenario, 'txPower')
+    TX_POWER_VEC = scenario.txPower;                       % 1×N (Watts)
+    assert(numel(TX_POWER_VEC) == numAgents, ...
+        "txPower has %d values but expected %d (one per UAV)", numel(TX_POWER_VEC), numAgents);
+else
+    TX_POWER_VEC = 0.1 * ones(1, numAgents);
+end
+if isfield(scenario, 'useSinrComms')
+    USE_SINR_COMMS = logical(scenario.useSinrComms);
+else
+    USE_SINR_COMMS = false;
+end
+if isfield(scenario, 'sinrThreshold')
+    SINR_THRESHOLD = scenario.sinrThreshold;               % dB
+else
+    SINR_THRESHOLD = 0;
+end
+if isfield(scenario, 'pathLossExponent')
+    PATH_LOSS_EXPONENT = scenario.pathLossExponent;
+else
+    PATH_LOSS_EXPONENT = 2.0;
+end
+if isfield(scenario, 'ambientTemp')
+    AMBIENT_TEMP = scenario.ambientTemp;                   % Kelvin
+else
+    AMBIENT_TEMP = 290.0;
+end
+if isfield(scenario, 'centerFreq')
+    CENTER_FREQ = scenario.centerFreq;                     % Hz
+else
+    CENTER_FREQ = 2.4e9;
+end
+if isfield(scenario, 'bandwidth')
+    BANDWIDTH = scenario.bandwidth;                        % Hz
+else
+    BANDWIDTH = 20e6;
+end
+
 % ---- Build domain --------------------------------------------------------
 dom = rectangularPrism;
 dom = dom.initialize([DOMAIN_MIN; DOMAIN_MAX], REGION_TYPE.DOMAIN, "Guidance Domain");
@@ -134,6 +174,7 @@ for ii = 1:numAgents
     ag = agent;
     ag = ag.initialize(pos, geom, sensor, COMMS_RANGE_VEC(ii), MAX_ITER, ...
                        INITIAL_STEP_SIZE, sprintf("UAV %d", ii));
+    ag.txPower = TX_POWER_VEC(ii); % SINR comms model transmit power (W)
     agentList{ii} = ag;
 end
 
@@ -153,6 +194,7 @@ end
 % ---- Initialise simulation (plots and video disabled) --------------------
 obj = obj.initialize(dom, agentList, BARRIER_GAIN, BARRIER_EXPONENT, ...
                      MIN_ALT, TIMESTEP, MAX_ITER, obstacleList, false, false, ...
-                     USE_DOUBLE_INTEGRATOR, DAMPING_COEFF, USE_FIXED_TOPOLOGY);
+                     USE_DOUBLE_INTEGRATOR, DAMPING_COEFF, USE_FIXED_TOPOLOGY, false, ...
+                     USE_SINR_COMMS, SINR_THRESHOLD, PATH_LOSS_EXPONENT, AMBIENT_TEMP, CENTER_FREQ, BANDWIDTH);
 
 end

@miSim/initializeFromInits.m

@@ -47,6 +47,9 @@ for ii = 1:numAgents
     ag = agent;
     ag = ag.initialize(pos, geom, sensor, inits.comRange(ii), inits.maxIter, ...
                        inits.initialStepSize(ii), sprintf("UAV %d", ii));
+    if isfield(inits, 'txPower')
+        ag.txPower = inits.txPower(ii); % SINR comms model transmit power (W)
+    end
     agentList{ii} = ag;
 end
 
@@ -78,10 +81,41 @@ if isfield(inits, 'useFixedTopology')
 else
     useFixedTopology = false;
 end
+if isfield(inits, 'useSinrComms')
+    useSinrComms = logical(inits.useSinrComms);
+else
+    useSinrComms = false;
+end
+if isfield(inits, 'sinrThreshold')
+    sinrThreshold = inits.sinrThreshold;
+else
+    sinrThreshold = 0;
+end
+if isfield(inits, 'pathLossExponent')
+    pathLossExponent = inits.pathLossExponent;
+else
+    pathLossExponent = 2.0;
+end
+if isfield(inits, 'ambientTemp')
+    ambientTemp = inits.ambientTemp;
+else
+    ambientTemp = 290.0;
+end
+if isfield(inits, 'centerFreq')
+    centerFreq = inits.centerFreq;
+else
+    centerFreq = 2.4e9;
+end
+if isfield(inits, 'bandwidth')
+    bandwidth = inits.bandwidth;
+else
+    bandwidth = 20e6;
+end
 
 % ---- Initialize simulation (plots and video disabled) ------------------------
 obj = obj.initialize(dom, agentList, inits.barrierGain, inits.barrierExponent, ...
                      inits.minAlt, inits.timestep, inits.maxIter, obstacleList, ...
-                     false, false, useDoubleIntegrator, dampingCoeff, useFixedTopology);
+                     false, false, useDoubleIntegrator, dampingCoeff, useFixedTopology, false, ...
+                     useSinrComms, sinrThreshold, pathLossExponent, ambientTemp, centerFreq, bandwidth);
 
 end

@miSim/miSim.m

@@ -21,6 +21,15 @@ classdef miSim
         dampingCoeff = 2.0; % velocity-proportional damping for double-integrator mode
         useFixedTopology = false; % false = lesser neighbor (dynamic), true = fixed initial topology
         optimizeSensorPointing = false; % false = fixed sensor tilt/azimuth, true = optimize tilt/azimuth via gradient ascent
+        % Communications model selection and SINR-model parameters.
+        % useSinrComms = false -> fixed-radius comms (comRange / commsGeometry).
+        % useSinrComms = true  -> SINR/path-loss comms (txPower + params below).
+        useSinrComms = false;
+        sinrThreshold = 0;        % SINR threshold for connectivity & CBF maintenance (dB)
+        pathLossExponent = 2.0;   % path-loss exponent n in S = P / (K * d^n)
+        ambientTemp = 290.0;      % ambient temperature (K) for thermal noise N = k_B*T*B
+        centerFreq = 2.4e9;       % carrier frequency (Hz); sets path-loss offset K = (4*pi*f_c/c)^2
+        bandwidth = 20e6;         % channel bandwidth (Hz) for thermal noise N = k_B*T*B
         artifactName = "";
         f; % main plotting tiled layout figure
         fPerf; % performance plot figure
@@ -70,13 +79,14 @@ classdef miSim
             obj.obstacles = {rectangularPrism};
             obj.agents = {agent};
         end
-        [obj] = initialize(obj, domain, agents, barrierGain, barrierExponent, minAlt, timestep, maxIter, obstacles, makePlots, makeVideo, useDoubleIntegrator, dampingCoeff, useFixedTopology);
+        [obj] = initialize(obj, domain, agents, barrierGain, barrierExponent, minAlt, timestep, maxIter, obstacles, makePlots, makeVideo, useDoubleIntegrator, dampingCoeff, useFixedTopology, optimizeSensorPointing, useSinrComms, sinrThreshold, pathLossExponent, ambientTemp, centerFreq, bandwidth);
         [obj] = initializeFromCsv(obj, csvPath);
         [obj] = initializeFromInits(obj, initsPath);
         [obj] = plotFromSimHist(obj, initsPath, histPath);
         [obj] = run(obj);
         [obj] = lesserNeighbor(obj);
         [obj] = constrainMotion(obj);
+        [sinr, grad] = sinrLink(obj, positions, rxIdx, txIdx);
         [obj] = partition(obj);
         [obj] = updateAdjacency(obj);
         [obj] = plot(obj);

@miSim/plotGraph.m

@@ -9,20 +9,44 @@ function obj = plotGraph(obj)
     % Form graph from adjacency matrix
     G = graph(obj.constraintAdjacencyMatrix, "omitselfloops");
 
-    % Plot graph object
+    % Resolve the target axes for the network graph tile
     if isnan(obj.networkGraphIndex)
-        hold(obj.f.CurrentAxes, "on");
+        ax = obj.f.CurrentAxes;
-        o = plot(obj.f.CurrentAxes, G, "LineStyle", "--", "EdgeColor", "g", "NodeColor", "k", "LineWidth", 2);
-        hold(obj.f.CurrentAxes, "off");
     else
-        hold(obj.f.Children(1).Children(obj.networkGraphIndex(1)), "on");
+        ax = obj.f.Children(1).Children(obj.networkGraphIndex(1));
-        o = plot(obj.f.Children(1).Children(obj.networkGraphIndex(1)), G, "LineStyle", "--", "EdgeColor", "g", "NodeColor", "k", "LineWidth", 2);
+    end
-        hold(obj.f.Children(1).Children(obj.networkGraphIndex(1)), "off");
+
-        if size(obj.networkGraphIndex, 2) > 1
+    % Plot graph object
-            for ii = 2:size(ind, 2)
+    hold(ax, "on");
-                o = [o; copyobj(o(1), obj.f.Children(1).Children(obj.networkGraphIndex(ii)))];
+    o = plot(ax, G, "LineStyle", "--", "EdgeColor", "g", "NodeColor", "k", "LineWidth", 2);
-            end
+    hold(ax, "off");
+    if ~isnan(obj.networkGraphIndex) && size(obj.networkGraphIndex, 2) > 1
+        for ii = 2:size(obj.networkGraphIndex, 2)
+            o = [o; copyobj(o(1), obj.f.Children(1).Children(obj.networkGraphIndex(ii)))];
         end
     end
+
+    % In SINR comms mode, label each edge with the connection's SINR (dB) and
+    % report the connectivity threshold as a subtitle on the tile. The
+    % fixed-radius model is left unchanged (no edge labels, no subtitle).
+    if obj.useSinrComms
+        endNodes = G.Edges.EndNodes;   % each row [lo hi]; graph stores lo < hi
+        nAgents = size(obj.agents, 1);
+        positions = zeros(nAgents, 3);
+        for kk = 1:nAgents
+            positions(kk, :) = obj.agents{kk}.pos;
+        end
+        % Directional convention (matches updateAdjacency/constrainMotion):
+        % the lower-index node is the receiver, the higher-index node the
+        % transmitter, with interference from all other agents at the receiver.
+        edgeLabels = strings(size(endNodes, 1), 1);
+        for ee = 1:size(endNodes, 1)
+            sinrLin = obj.sinrLink(positions, endNodes(ee, 1), endNodes(ee, 2));
+            edgeLabels(ee) = sprintf("%.1f dB", 10 * log10(sinrLin));
+        end
+        o(1).EdgeLabel = edgeLabels;
+        subtitle(ax, sprintf("SINR threshold: %.1f dB", obj.sinrThreshold));
+    end
+
     obj.graphPlot = o;
-end
+end

@miSim/sinrLink.m

@@ -0,0 +1,101 @@
+function [sinr, grad] = sinrLink(obj, positions, rxIdx, txIdx)
+% SINRLINK  Linear SINR of the link txIdx -> rxIdx and its position gradient.
+%
+% Computes the signal-to-interference-plus-noise ratio seen at receiver rxIdx
+% for the signal transmitted by txIdx, treating every other agent as an
+% interferer at that receiver. Isotropic transmit/receive (no antenna gains).
+%
+% Returns the linear SINR and (optionally) its gradient with respect to every
+% agent position, grad(a, :) = d(SINR)/d(p_a). The value is used by
+% updateAdjacency (connectivity) and both the value and gradient by
+% constrainMotion (the SINR CBF barrier).
+%
+% Model (linear power domain), receiver r = rxIdx, transmitter t = txIdx:
+%   S    = P_t / (K * d_tr^n)                 % received signal at r from t (W)
+%   I    = sum_{k != t,r} P_k / (K * d_kr^n)  % interference at r from others (W)
+%   N    = k_B * T * B                        % thermal noise (W)
+%   SINR = S / (N + I)
+% with K = (4*pi*f_c/c)^2 and physical constants baked in below. The only
+% tunables are per-agent txPower (P), pathLossExponent (n), ambientTemp (T),
+% all read from obj; the SINR threshold is applied by the callers.
+
+    arguments (Input)
+        obj (1, 1) {mustBeA(obj, "miSim")};
+        positions (:, 3) double;
+        rxIdx (1, 1) double;
+        txIdx (1, 1) double;
+    end
+    arguments (Output)
+        sinr (1, 1) double;
+        grad (:, 3) double;
+    end
+
+    % Universal physical constants
+    k_B = 1.380649e-23;          % Boltzmann constant (J/K)
+    c   = 3e8;                   % speed of light (m/s)
+
+    % System parameters
+    f_c = obj.centerFreq;        % carrier frequency (Hz)
+    B   = obj.bandwidth;         % channel bandwidth (Hz)
+    K   = (4 * pi * f_c / c)^2;  % free-space path-loss reference constant
+
+    n  = obj.pathLossExponent;
+    T  = obj.ambientTemp;
+    d0 = 1.0;                    % near-field distance floor (m)
+
+    nAgents = size(positions, 1);
+    grad = zeros(nAgents, 3);
+
+    r  = rxIdx;
+    t  = txIdx;
+    pr = positions(r, :);
+
+    % Thermal noise (always > 0, so the denominator never vanishes)
+    N = k_B * T * B;
+
+    % Signal term S (source = transmitter t)
+    P_t    = obj.agents{t}.txPower;
+    dvec_t = positions(t, :) - pr;
+    d_t    = max(norm(dvec_t), d0);
+    S      = P_t / (K * d_t^n);
+
+    % Interference I = sum of received powers from every other agent at r
+    I = 0.0;
+    for k = 1:nAgents
+        if k == r || k == t
+            continue;
+        end
+        d_k = max(norm(positions(k, :) - pr), d0);
+        I   = I + obj.agents{k}.txPower / (K * d_k^n);
+    end
+
+    D    = N + I;       % denominator: noise + interference
+    sinr = S / D;
+
+    % ---- Gradient (skip unless requested) -------------------------------
+    % For a received term P_x/(K*d_xr^n):
+    %   d(term)/dp_x = -n*term/d_xr^2 * (p_x - p_r),  d(term)/dp_r = -d(term)/dp_x
+    if nargout > 1
+        % Transmitter affects S only: dSINR/dp_t = (dS/dp_t)/D
+        dS_dpt = (-n * S / (d_t^2)) * dvec_t;
+        grad(t, :) = dS_dpt / D;
+
+        % Interferers affect I only; accumulate the receiver's I-contribution
+        dI_dpr = zeros(1, 3);
+        for k = 1:nAgents
+            if k == r || k == t
+                continue;
+            end
+            dvec_k    = positions(k, :) - pr;
+            d_k       = max(norm(dvec_k), d0);
+            term_k    = obj.agents{k}.txPower / (K * d_k^n);
+            dterm_dpk = (-n * term_k / (d_k^2)) * dvec_k;
+            grad(k, :) = (-S / (D^2)) * dterm_dpk;      % dSINR/dp_k
+            dI_dpr     = dI_dpr - dterm_dpk;            % d(term_k)/dp_r = -d(term_k)/dp_k
+        end
+
+        % Receiver affects both S and I
+        dS_dpr = -dS_dpt;
+        grad(r, :) = dS_dpr / D - (S / (D^2)) * dI_dpr;
+    end
+end

@miSim/updateAdjacency.m

@@ -6,16 +6,38 @@ function obj = updateAdjacency(obj)
         obj (1, 1) {mustBeA(obj, "miSim")};
     end
 
-    % Initialize assuming only self-connections
+    nAgents = size(obj.agents, 1);
-    A = true(size(obj.agents, 1));
 
-    % Check lower triangle off-diagonal connections
+    % Initialize assuming all agents are connected
-    for ii = 2:size(A, 1)
+    A = true(nAgents);
-        for jj = 1:(ii - 1)
+
-            % Check that agents are not out of range
+    if ~obj.useSinrComms
-            if norm(obj.agents{ii}.pos - obj.agents{jj}.pos) > min([obj.agents{ii}.commsGeometry.radius, obj.agents{jj}.commsGeometry.radius])
+        % Fixed-radius model: pair connected iff separation is within the
-                A(ii, jj) = false; % comm range violation
+        % smaller of the two comms radii.
-                continue;
+        for ii = 2:nAgents
+            for jj = 1:(ii - 1)
+                if norm(obj.agents{ii}.pos - obj.agents{jj}.pos) > min([obj.agents{ii}.commsGeometry.radius, obj.agents{jj}.commsGeometry.radius])
+                    A(ii, jj) = false; % comm range violation
+                    continue;
+                end
+            end
+        end
+    else
+        % SINR model: pair (ii, jj) connected iff the lower-index agent (jj)
+        % receives the higher-index agent's (ii) signal above the SINR
+        % threshold, with interference from all other agents at the receiver.
+        gammaLin = 10^(obj.sinrThreshold / 10); % dB threshold -> linear
+        positions = zeros(nAgents, 3);
+        for kk = 1:nAgents
+            positions(kk, :) = obj.agents{kk}.pos;
+        end
+        for ii = 2:nAgents
+            for jj = 1:(ii - 1)
+                sinr = obj.sinrLink(positions, jj, ii); % receiver jj, transmitter ii
+                if sinr < gammaLin
+                    A(ii, jj) = false; % SINR below threshold
+                    continue;
+                end
             end
         end
     end

@miSim/writeInits.m

@@ -47,6 +47,7 @@ function writeInits(obj)
     tilt = cellfun(@(x) x.sensorModel.tilt, obj.agents);
     azimuth = cellfun(@(x) x.sensorModel.azimuth, obj.agents);
     comRanges = cellfun(@(x) x.commsGeometry.radius, obj.agents);
+    txPower = cellfun(@(x) x.txPower, obj.agents);
     initialStepSize = cellfun(@(x) x.initialStepSize, obj.agents);
     pos = cell2mat(cellfun(@(x) x.pos, obj.agents, 'UniformOutput', false));
     obsMinCorners = cell2mat(cellfun(@(x) x.minCorner, userObstacles, 'UniformOutput', false));
@@ -59,6 +60,8 @@ function writeInits(obj)
                     "barrierGain", obj.barrierGain, "barrierExponent", obj.barrierExponent, "numObstacles", numInputObs, ...
                     "numAgents", size(obj.agents, 1), "collisionRadius", collisionRadii, "comRange", comRanges, ...
                     "useDoubleIntegrator", obj.useDoubleIntegrator, "dampingCoeff", obj.dampingCoeff, "useFixedTopology", obj.useFixedTopology, ...
+                    "useSinrComms", obj.useSinrComms, "sinrThreshold", obj.sinrThreshold, "pathLossExponent", obj.pathLossExponent, "ambientTemp", obj.ambientTemp, ...
+                    "centerFreq", obj.centerFreq, "bandwidth", obj.bandwidth, "txPower", txPower, ... % SINR comms model parameters
                     "tilt", tilt, "azimuth", azimuth, ... % joint sensor parameters
                     "alphaDist", alphaDist, "betaDist", betaDist, "alphaTilt", alphaTilt, "betaTilt", betaTilt, ... % sigmoid sensor parameters
                     "lossExponent", lossExponent, "P_TX", P_TX, "BW", BW, "f_c", f_c, "G_RX_dBi", G_RX_dBi, "beamwidthExponent", beamwidthExponent, ... % RF sensor parameters

aerpaw/config/scenario.csv

@@ -1,2 +1,2 @@
-timestep, maxIter, minAlt, discretizationStep, protectedRange, initialStepSize, barrierGain, barrierExponent, collisionRadius, comRange, alphaDist, betaDist, alphaTilt, betaTilt, domainMin, domainMax, objectivePos, objectiveVar, sensorPerformanceMinimum, initialPositions, numObstacles, obstacleMin, obstacleMax, useDoubleIntegrator, dampingCoeff, useFixedTopology
+timestep, maxIter, minAlt, discretizationStep, protectedRange, initialStepSize, barrierGain, barrierExponent, collisionRadius, comRange, alphaDist, betaDist, alphaTilt, betaTilt, domainMin, domainMax, objectivePos, objectiveVar, sensorPerformanceMinimum, initialPositions, numObstacles, obstacleMin, obstacleMax, useDoubleIntegrator, dampingCoeff, useFixedTopology, txPower, useSinrComms, sinrThreshold, pathLossExponent, ambientTemp, centerFreq, bandwidth
-1, 80, 35.0, 0.1, 2.0, 6, 1, 1, "8.0, 8.0", "35.0, 35.0", "80.0, 50.0", "0.25, 1.0", "8.0, 25.0", "0.1, 0.02", "0.0, 0.0, 0.0", "100.0, 100.0, 100.0", "60.0, 80.0, 45.0, 70.0", "70, 15, 15, 20, 20, 15, 15, 70", 0.15, "15.0, 15.0, 50.0, 40.0, 10.0, 45.0", 8, "0.0, 30.0, 0.0, 42.0, 30.0, 0.0, 84.0, 30.0, 0.0, 13.0, 60.0, 0.0, 55.0, 60.0, 0.0, 0.0, 90, 0.0, 42.0, 90.0, 0.0, 84.0, 90.0, 0.0", "16.0, 40.0, 100.0, 58.0, 40.0, 100.0, 100.0, 40.0, 100.0, 29.0, 70.0, 100.0, 71.0, 70.0, 100.0, 16.0, 100.0, 100.0, 58.0, 100.0, 100.0, 100.0, 100.0, 100.0", 0, 2.0, 1
+1, 80, 35.0, 0.1, 2.0, 6, 1, 1, "8.0, 8.0", "35.0, 35.0", "80.0, 50.0", "0.25, 1.0", "8.0, 25.0", "0.1, 0.02", "0.0, 0.0, 0.0", "100.0, 100.0, 100.0", "60.0, 80.0, 45.0, 70.0", "70, 15, 15, 20, 20, 15, 15, 70", 0.15, "15.0, 15.0, 50.0, 40.0, 10.0, 45.0", 8, "0.0, 30.0, 0.0, 42.0, 30.0, 0.0, 84.0, 30.0, 0.0, 13.0, 60.0, 0.0, 55.0, 60.0, 0.0, 0.0, 90, 0.0, 42.0, 90.0, 0.0, 84.0, 90.0, 0.0", "16.0, 40.0, 100.0, 58.0, 40.0, 100.0, 100.0, 40.0, 100.0, 29.0, 70.0, 100.0, 71.0, 70.0, 100.0, 16.0, 100.0, 100.0, 58.0, 100.0, 100.0, 100.0, 100.0, 100.0", 0, 2.0, 1, "0.2, 0.1", 0, 5.0, 2.5, 290.0, 2.4e9, 20e6

aerpaw/controller.m

@@ -50,7 +50,7 @@ else
 end
 
 % Load guidance scenario from CSV (parameters for guidance_step)
-NUM_SCENARIO_PARAMS = 55;
+NUM_SCENARIO_PARAMS = 65;
 MAX_OBSTACLES_CTRL  = int32(8);
 scenarioParams = zeros(1, NUM_SCENARIO_PARAMS);
 obstacleMin    = zeros(MAX_OBSTACLES_CTRL, 3);

aerpaw/guidance_step.m

@@ -17,7 +17,8 @@ function nextPositions = guidance_step(currentPositions, isInit, ...
 %                       Flat array of guidance parameters (compiled path).
 %                       On MATLAB path this is ignored; parameters are loaded
 %                       from scenario.csv via initializeFromCsv instead.
-%                       Index mapping (1-based):
+%                       Index mapping (1-based; authoritative map in
+%                       aerpaw/impl/controller_impl.h):
 %                         1  timestep            9-12  collisionRadius[1:4]
 %                         2  maxIter            13-16  comRange[1:4]
 %                         3  minAlt             17-20  alphaDist[1:4]
@@ -26,12 +27,20 @@ function nextPositions = guidance_step(currentPositions, isInit, ...
 %                         6  initialStepSize    29-32  betaTilt[1:4]
 %                         7  barrierGain        33-35  domainMin
 %                         8  barrierExponent    36-38  domainMax
-%                                               39-40  objectivePos
+%                                               39     numObjectiveComponents
-%                                               41-44  objectiveVar (2x2, col-major)
+%                                               40-43  objectivePos [x1,y1,x2,y2]
-%                                               45     sensorPerformanceMinimum
+%                                               44-51  objectiveVar [per component]
-%                                               46     useDoubleIntegrator
+%                                               52     sensorPerformanceMinimum
-%                                               47     dampingCoeff
+%                                               53     useDoubleIntegrator
-%                                               48     useFixedTopology
+%                                               54     dampingCoeff
+%                                               55     useFixedTopology
+%                                               56-59  txPower[1:4]
+%                                               60     useSinrComms
+%                                               61     sinrThreshold (dB)
+%                                               62     pathLossExponent
+%                                               63     ambientTemp (K)
+%                                               64     centerFreq (Hz)
+%                                               65     bandwidth (Hz)
 %   obstacleMin       (MAX_OBSTACLES × 3) double  column-major obstacle corners (compiled path)
 %   obstacleMax       (MAX_OBSTACLES × 3) double
 %   numObstacles      (1,1) int32                 actual obstacle count
@@ -101,6 +110,13 @@ if isInit
         USE_DOUBLE_INTEGRATOR       = logical(scenarioParams(53));
         DAMPING_COEFF               = scenarioParams(54);
         USE_FIXED_TOPOLOGY          = logical(scenarioParams(55));
+        TX_POWER_VEC                = scenarioParams(56:59); % per-UAV [1:MAX_CLIENTS] (W)
+        USE_SINR_COMMS              = logical(scenarioParams(60));
+        SINR_THRESHOLD              = scenarioParams(61);    % dB
+        PATH_LOSS_EXPONENT          = scenarioParams(62);
+        AMBIENT_TEMP                = scenarioParams(63);    % Kelvin
+        CENTER_FREQ                 = scenarioParams(64);    % Hz
+        BANDWIDTH                   = scenarioParams(65);    % Hz
 
         % --- Build domain geometry ---
         dom = rectangularPrism;
@@ -141,6 +157,7 @@ if isInit
             ag = agent;
             ag = ag.initialize(pos, geom, sensor, COMMS_RANGE_VEC(ii), MAX_ITER, ...
                                INITIAL_STEP_SIZE, sprintf("UAV %d", ii));
+            ag.txPower = TX_POWER_VEC(ii); % SINR comms model transmit power (W)
             agentList{ii} = ag;
         end
 
@@ -158,7 +175,8 @@ if isInit
         sim = miSim;
         sim = sim.initialize(dom, agentList, BARRIER_GAIN, BARRIER_EXPONENT, ...
                              MIN_ALT, TIMESTEP, MAX_ITER, obstacleList, false, false, ...
-                             USE_DOUBLE_INTEGRATOR, DAMPING_COEFF, USE_FIXED_TOPOLOGY);
+                             USE_DOUBLE_INTEGRATOR, DAMPING_COEFF, USE_FIXED_TOPOLOGY, false, ...
+                             USE_SINR_COMMS, SINR_THRESHOLD, PATH_LOSS_EXPONENT, AMBIENT_TEMP, CENTER_FREQ, BANDWIDTH);
     end
 
     % On the init call return current positions unchanged
@@ -187,8 +205,13 @@ else
     % 2. Advance timestep counter
     sim.timestepIndex = sim.timestepIndex + 1;
 
-    % 3. Update communications topology (Lesser Neighbour Assignment)
+    % 3. Update communications topology (Lesser Neighbour Assignment).
+    % Refresh the adjacency graph from current positions first so connectivity
+    % (fixed-radius or SINR) tracks the agents as they move; otherwise the graph
+    % would be frozen at init on the compiled path (the MATLAB sim refreshes it
+    % in @miSim/run.m). Skip when topology is fixed.
     if ~sim.useFixedTopology
+        sim = sim.updateAdjacency();
         sim = sim.lesserNeighbor();
     end
 

aerpaw/impl/controller_impl.cpp

@@ -238,8 +238,8 @@ int loadScenario(const char* filename, double* params) {
     strncpy(copy, line, sizeof(copy) - 1);
     copy[sizeof(copy) - 1] = '\0';
 
-    char* fields[32];
+    char* fields[40];
-    int nf = splitCSVRow(copy, fields, 32);
+    int nf = splitCSVRow(copy, fields, 40);
     if (nf < 26) {
         fprintf(stderr, "loadScenario: expected >=26 columns, got %d\n", nf);
         return 0;
@@ -376,8 +376,71 @@ int loadScenario(const char* filename, double* params) {
         params[54] = atof(trimField(tmp));
     }
 
+    // ---- SINR communications model (columns 26–30; optional) ----
+    // Defaults mirror @miSim/initializeFromCsv.m so a CSV predating the SINR
+    // model still loads (useSinrComms stays 0 -> fixed-radius path is used).
+    //   txPower[1:4] -> params[55:58];  useSinrComms -> 59;
+    //   sinrThreshold (dB) -> 60;  pathLossExponent -> 61;  ambientTemp (K) -> 62;
+    //   centerFreq (Hz) -> 63;  bandwidth (Hz) -> 64.
+    params[55] = 0.1; params[56] = 0.1; params[57] = 0.1; params[58] = 0.1;
+    params[59] = 0.0;     // useSinrComms
+    params[60] = 0.0;     // sinrThreshold (dB)
+    params[61] = 2.0;     // pathLossExponent
+    params[62] = 290.0;   // ambientTemp (K)
+    params[63] = 2.4e9;   // centerFreq (Hz)
+    params[64] = 20e6;    // bandwidth (Hz)
+
+    // txPower: column 26 (per-UAV, up to MAX_CLIENTS_PER_PARAM values, zero-padded)
+    if (nf > 26) {
+        char tmp[256]; strncpy(tmp, fields[26], sizeof(tmp) - 1); tmp[sizeof(tmp)-1] = '\0';
+        char* t = trimField(tmp);
+        double vals[4] = {0, 0, 0, 0};
+        int count = 0;
+        char* tok = strtok(t, ",");
+        while (tok && count < MAX_CLIENTS_PER_PARAM) {
+            vals[count++] = atof(tok);
+            tok = strtok(nullptr, ",");
+        }
+        if (count > 0) {
+            for (int k = 0; k < MAX_CLIENTS_PER_PARAM; k++) params[55 + k] = vals[k];
+        }
+    }
+
+    // useSinrComms: column 27
+    if (nf > 27) {
+        char tmp[64]; strncpy(tmp, fields[27], sizeof(tmp) - 1); tmp[sizeof(tmp)-1] = '\0';
+        params[59] = atof(trimField(tmp));
+    }
+    // sinrThreshold: column 28 (dB)
+    if (nf > 28) {
+        char tmp[64]; strncpy(tmp, fields[28], sizeof(tmp) - 1); tmp[sizeof(tmp)-1] = '\0';
+        params[60] = atof(trimField(tmp));
+    }
+    // pathLossExponent: column 29
+    if (nf > 29) {
+        char tmp[64]; strncpy(tmp, fields[29], sizeof(tmp) - 1); tmp[sizeof(tmp)-1] = '\0';
+        params[61] = atof(trimField(tmp));
+    }
+    // ambientTemp: column 30 (K)
+    if (nf > 30) {
+        char tmp[64]; strncpy(tmp, fields[30], sizeof(tmp) - 1); tmp[sizeof(tmp)-1] = '\0';
+        params[62] = atof(trimField(tmp));
+    }
+    // centerFreq: column 31 (Hz)
+    if (nf > 31) {
+        char tmp[64]; strncpy(tmp, fields[31], sizeof(tmp) - 1); tmp[sizeof(tmp)-1] = '\0';
+        params[63] = atof(trimField(tmp));
+    }
+    // bandwidth: column 32 (Hz)
+    if (nf > 32) {
+        char tmp[64]; strncpy(tmp, fields[32], sizeof(tmp) - 1); tmp[sizeof(tmp)-1] = '\0';
+        params[64] = atof(trimField(tmp));
+    }
+
     printf("Loaded scenario: domain [%g,%g,%g] to [%g,%g,%g], %d objective component(s)\n",
            params[32], params[33], params[34], params[35], params[36], params[37], (int)params[38]);
+    printf("Comms model: %s (SINR threshold %g dB, path-loss exp %g, T=%g K, f_c=%g Hz, BW=%g Hz)\n",
+           params[59] != 0.0 ? "SINR" : "fixed-radius", params[60], params[61], params[62], params[63], params[64]);
     return 1;
 }
 

aerpaw/impl/controller_impl.h

@@ -34,7 +34,14 @@ int loadTargets(const char* filename, double* targets, int maxClients);
 //   52    useDoubleIntegrator  (0=single-integrator, 1=double-integrator)
 //   53    dampingCoeff
 //   54    useFixedTopology     (0=dynamic lesser-neighbor, 1=fixed)
-#define NUM_SCENARIO_PARAMS 55
+//   55-58 txPower[1:4]         (per-UAV transmit power, Watts; SINR comms model)
+//   59    useSinrComms         (0=fixed-radius comms, 1=SINR/path-loss comms)
+//   60    sinrThreshold        (SINR connectivity/CBF threshold, dB)
+//   61    pathLossExponent     (path-loss exponent n)
+//   62    ambientTemp          (ambient temperature, K; thermal noise)
+//   63    centerFreq           (carrier frequency, Hz; path-loss offset)
+//   64    bandwidth            (channel bandwidth, Hz; thermal noise)
+#define NUM_SCENARIO_PARAMS 65
 #define MAX_CLIENTS_PER_PARAM 4
 // Maximum number of obstacles (upper bound for pre-allocated arrays).
 #define MAX_OBSTACLES 8

aerpaw/results/resultsAnalysis.m

@@ -45,6 +45,9 @@ for ii = 1:size(agents, 1)
     collisionGeometry = collisionGeometry.initialize(params.initialPositions((((ii - 1) * 3) + 1):(ii * 3)), params.collisionRadius(ii), REGION_TYPE.COLLISION, sprintf("Agent %d collision geometry", ii));
 
     agents{ii} = agents{ii}.initialize(params.initialPositions((((ii - 1) * 3) + 1):(ii * 3)), collisionGeometry, sensorModel, params.comRange(ii), params.maxIter, params.initialStepSize, 5.0, sprintf("Agent %d", ii), plotCommsGeometry);
+    if isfield(params, 'txPower')
+        agents{ii}.txPower = params.txPower(ii); % SINR comms model transmit power (W)
+    end
 end
 
 % Create obstacles
@@ -54,9 +57,22 @@ for ii = 1:size(obstacles, 1)
     obstacles{ii} = obstacles{ii}.initialize([params.obstacleMin((((ii - 1) * 3) + 1):(ii * 3)); params.obstacleMax((((ii - 1) * 3) + 1):(ii * 3))], "OBSTACLE", sprintf("Obstacle %d", ii));
 end
 
-% Set up simulation
+% SINR communications model parameters (optional CSV columns; default to the
+% fixed-radius path so existing scenarios are unaffected)
+if isfield(params, 'useSinrComms');     useSinrComms = logical(params.useSinrComms); else; useSinrComms = false; end
+if isfield(params, 'sinrThreshold');    sinrThreshold = params.sinrThreshold;        else; sinrThreshold = 0;        end
+if isfield(params, 'pathLossExponent'); pathLossExponent = params.pathLossExponent;  else; pathLossExponent = 2.0;    end
+if isfield(params, 'ambientTemp');      ambientTemp = params.ambientTemp;            else; ambientTemp = 290.0;      end
+if isfield(params, 'centerFreq');       centerFreq = params.centerFreq;              else; centerFreq = 2.4e9;       end
+if isfield(params, 'bandwidth');        bandwidth = params.bandwidth;                else; bandwidth = 20e6;         end
+
+% Set up simulation. The four args after makeVideo (useDoubleIntegrator,
+% dampingCoeff, useFixedTopology, optimizeSensorPointing) are kept at their
+% prior effective defaults to preserve existing analysis behavior; only the
+% SINR comms parameters are threaded through from the scenario.
 sim = miSim;
-sim = sim.initialize(domain, agents, params.barrierGain, params.barrierExponent, params.minAlt, params.timestep, params.maxIter, obstacles, makePlots, makeVideo);
+sim = sim.initialize(domain, agents, params.barrierGain, params.barrierExponent, params.minAlt, params.timestep, params.maxIter, obstacles, makePlots, makeVideo, ...
+                     false, 2.0, false, false, useSinrComms, sinrThreshold, pathLossExponent, ambientTemp, centerFreq, bandwidth);
 
 % Save simulation parameters to output file
 sim.writeInits();

test/test_miSim.m

@@ -815,7 +815,7 @@ classdef test_miSim < matlab.unittest.TestCase
             % Run the simulation
             tc.testClass.run();
         end
-        function test_communications_constraint(tc)
+        function test_communications_constraint_SINR_threshold(tc)
             % No obstacles
             % Fixed two agents initial conditions
             % Negligible collision geometries
@@ -843,6 +843,67 @@ classdef test_miSim < matlab.unittest.TestCase
             % Initialize obstacles
             tc.obstacles = {};
             
+            % Initialize agents
+            tc.maxIter = 50;
+            tc.commsRanges = 4 * ones(size(tc.agents)); % unused in SINR mode; kept for parity with the fixed-radius variant
+            tc.agents{1} = tc.agents{1}.initialize(tc.domain.center + d, geometry1, tc.sensor, tc.commsRanges(1), tc.maxIter, tc.initialStepSize, tc.initialMaxAngleStepSize);
+            tc.agents{2} = tc.agents{2}.initialize(tc.domain.center - d, geometry2, tc.sensor, tc.commsRanges(2), tc.maxIter, tc.initialStepSize, tc.initialMaxAngleStepSize);
+
+            % SINR communications model parameters. With isotropic links and only
+            % two agents (no interference) the link is noise-limited:
+            %   SINR = Ptx / ((4*pi*fc/c)^2 * d^n * kB*T*B)
+            % Pick the threshold so the SINR connectivity boundary sits at an
+            % effective range of ~4 m, mirroring the commsRange used by the
+            % fixed-radius variant of this test (so the two agents still cannot
+            % reach their objectives without breaking connectivity).
+            useSinrComms     = true;
+            txPower          = 0.1;     % transmit power per agent (W)
+            pathLossExponent = 2.0;
+            ambientTemp      = 290;     % K
+            centerFreq       = 2.4e9;   % Hz
+            bandwidth        = 20e6;    % Hz
+            effRange         = 4.0;     % desired effective comms range (m)
+            K_pl   = (4 * pi * centerFreq / 3e8)^2;            % free-space path-loss reference
+            noiseW = 1.380649e-23 * ambientTemp * bandwidth;   % thermal noise (W)
+            sinrThreshold = 10 * log10(txPower / (K_pl * effRange^pathLossExponent * noiseW)); % dB
+
+            tc.agents{1}.txPower = txPower;
+            tc.agents{2}.txPower = txPower;
+
+            % Initialize the simulation in SINR comms mode
+            tc.testClass = tc.testClass.initialize(tc.domain, tc.agents, tc.barrierGain, tc.barrierExponent, tc.minAlt, tc.timestep, tc.maxIter, tc.obstacles, tc.makePlots, tc.makeVideo, tc.useDoubleIntegrator, tc.dampingCoeff, tc.useFixedTopology, tc.optimizeSensorPointing, useSinrComms, sinrThreshold, pathLossExponent, ambientTemp, centerFreq, bandwidth);
+
+            % Run the simulation
+            tc.testClass = tc.testClass.run();
+        end
+        function test_communications_constraint_fixed_radius(tc)
+            % No obstacles
+            % Fixed two agents initial conditions
+            % Negligible collision geometries
+            % Non-standard domain with two objectives that will try to pull the
+            % agents apart
+            tc.minDimension = 10; % domain size
+            tc.domain = tc.domain.initialize([zeros(1, 3);tc.minDimension* ones(1, 3)], REGION_TYPE.DOMAIN, "Domain");
+
+            % make basic sensing objective
+            tc.domain.objective = tc.domain.objective.initialize(objectiveFunctionWrapper([2, 8; 8, 8]), tc.domain, tc.discretizationStep, tc.protectedRange);
+
+            % Initialize agent collision geometry
+            tc.agents = {agent; agent;};
+            tc.collisionRanges = .25 * ones(size(tc.agents));
+            d = [1, 0, 0];
+            geometry1 = spherical;
+            geometry2 = geometry1;
+            geometry1 = geometry1.initialize(tc.domain.center + d, tc.collisionRanges(1), REGION_TYPE.COLLISION);
+            geometry2 = geometry2.initialize(tc.domain.center - d, tc.collisionRanges(2), REGION_TYPE.COLLISION);
+
+            % Initialize agent sensor model
+            tc.sensor = sigmoidSensor;
+            tc.sensor = tc.sensor.initialize(tc.minDimension / 2, 3, 15, 3);
+
+            % Initialize obstacles
+            tc.obstacles = {};
+
             % Initialize agents
             tc.maxIter = 50;
             tc.commsRanges = 4 * ones(size(tc.agents)); % defined such that they cannot reach their objective without breaking connectivity
@@ -851,7 +912,7 @@ classdef test_miSim < matlab.unittest.TestCase
 
             % Initialize the simulation
             tc.testClass = tc.testClass.initialize(tc.domain, tc.agents, tc.barrierGain, tc.barrierExponent, tc.minAlt, tc.timestep, tc.maxIter, tc.obstacles, tc.makePlots, tc.makeVideo, tc.useDoubleIntegrator, tc.dampingCoeff, tc.useFixedTopology, tc.optimizeSensorPointing);
-            
+
             % Run the simulation
             tc.testClass = tc.testClass.run();
         end