first commit

lora_test.go

@@ -0,0 +1,60 @@
+package lora_test
+
+import (
+	"math"
+	"testing"
+	"time"
+
+	"github.com/soypat/lora"
+)
+
+func TestTimeOnAir(t *testing.T) {
+	const (
+		loraWANCodeRate       = lora.CR4_5
+		loraWANPreambleLength = 12
+	)
+	testCases := []struct {
+		desc     string
+		expected time.Duration
+		plen     int
+		cfg      lora.Config
+	}{
+		{
+			desc: "LoRaWAN 240bytes", // https://www.thethingsnetwork.org/airtime-calculator
+			cfg: lora.Config{
+				Bandwidth:      lora.BW125k,
+				Frequency:      915e6,
+				SpreadFactor:   lora.SF7,
+				HeaderType:     lora.HeaderExplicit,
+				CodingRate:     loraWANCodeRate,
+				CRC:            true,
+				PreambleLength: loraWANPreambleLength,
+			},
+			plen:     240,
+			expected: 394.5e3 * time.Microsecond,
+		},
+		{
+			desc: "LoRaWAN 5byte BW=500kHz", // https://www.thethingsnetwork.org/airtime-calculator
+			cfg: lora.Config{
+				Bandwidth:      lora.BW500k,
+				Frequency:      915e6,
+				SpreadFactor:   lora.SF7,
+				HeaderType:     lora.HeaderExplicit,
+				CodingRate:     loraWANCodeRate,
+				CRC:            true,
+				PreambleLength: loraWANPreambleLength,
+			},
+			plen:     10,
+			expected: 15.4e3 * time.Microsecond,
+		},
+	}
+	for _, tC := range testCases {
+		t.Run(tC.desc, func(t *testing.T) {
+			got := tC.cfg.TimeOnAir(tC.plen)
+			expect := tC.expected.Seconds()
+			if math.Abs(got.Seconds()-expect) > 10*expect/100 { // TODO: improve accuracy of TimeOnAir
+				t.Errorf("%s: got %s, expected %s", tC.desc, got.String(), tC.expected.String())
+			}
+		})
+	}
+}