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Campbell Manufacturing R410, RF400, RF415 Examples, H-6, 2 mi, 4 mi, 6 mi, 8 mi, 10 mi, 14 mi, 18 mi, 22 mi, 26 mi, 30 mi, Path Type, Path Type, Path Characteristics, Characteristics Selector

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Appendix H. Distance vs. Antenna Gain, Terrain, and Other Factors

Here is a table which gives calculated path loss (Lp) values at 900 MHz for the

2nd, 3rd, and 4th powers of distance; the equations (for 915 MHz) are:

				Lp (2nd power) = 95.8 + 20 ⋅ log ( d ) dB										(d in miles)
				Lp (3rd power) = 95.8 + 30 ⋅ log ( d )							dB			(d in miles)
				Lp (4th power) = 95.8 + 40 ⋅ log ( d )							dB			(d in miles)
				Example calculated Lp values (in dB)

	TABLE H-1. 900 MHz Distance vs. Path Loss (Lp in dB) per Three Path Types

Path Type	2 mi.	4 mi.	6 mi.		8 mi.		10 mi.		14 mi.		18 mi.		22 mi.		26 mi.	30 mi.
2nd power	102	108	111		114		116		119		121		123		124	125
3rd power	105	114	119		123		126		130		133		136		138	140
4th power	108	120	127		132		136		142		146		149		152	155
				The following table helps select a Path Type in the above “Distance vs. Path
				Loss” table to best fit your situation.

					TABLE H-2. Path Type vs. Path
					Characteristics Selector

				Path Type			Path Characteristics
				2nd power		Mountaintop to mountaintop
						or Tall antenna towers
						Line-of-sight
				3rd power		Dominantly line-of-sight
						Low antenna heights
						Some trees
				4th power		At water’s edge (very reflective)
						Across field of grain (reflective)
						Lots of Trees (absorptive)

Examples

Some examples will help illustrate the tradeoffs in a link analysis. These examples will all use the RF400 900 MHz radio, and will use –107 dBm as the required power level at the radio receiver. This is 3 dB higher than the quoted sensitivity of –110 dBm, which will give us a 3 dB margin.

Here’s the equation we will use, from the first page: Pt - Lt + Gt - Lp + Gr - Lr = Pr

Example #1

Antenex FG9023 antennas on each end, 20’ of LMR195 cable on one end, 10’ of LMR195 on the other end, antennas at 10’ height, fairly open terrain with a few trees. How far can I go?

Pt = 20 dBm

Lt = 20’ x (11.1 dB/100 ft) = 2.22 dB Gt = Gr = 3 dBd = 5.15 dBi

Lr = 10’ x (11.1 dB/100 ft) = 1.11 dB

H-6

Contents

RF400/RF410/RF415 Spread Spectrum Data Radio/Modem Warranty and Assistance – CAUTION – Page RF400 Series Table of Contents Introduction Quick Start Software Setup Troubleshooting D. Advanced Setup Standby Modes E. RF400 Series Port Pin Descriptions Short-Haul Modems H. Distance vs. Antenna Gain, Terrain, and Page Page RF400 Series Spread Spectrum Data Radio/Modems 1. Introduction 2. RF400 Series Specifications 3. Quick Start Step 1 – Set Up Base RF400 Step 2 – Set Up Remote RF400 Step 3 – LoggerNet/PC208W Set-up Step 4 – Connect 4. System Components 4.1 RF400 Series Data Radios 4.1.1 Indicator LEDs 4.1.2 Setup Menu 4.1.3 Networking 4.1.4Error Handling and Retries 4.1.4.2 Number of Retries 4.1.4.3 Number of Time Slots for Random Retry 4.1.4.4 Number of Bytes Transmitted before Delay 4.1.4.5 Sync Timer Setting 4.1.5 Received Signal Strength 4.2Power Supplies The RF400 series radio will sustain damage if the DC Pwr jack voltage ever exceeds Volts 4.3 Serial Cables 4.4 Antennas for the RF400 Series FCC OET Bulletin No. 63 (October 1993) approved antennas Page Page 4.5 Antenna Cables and Surge Protection 4.5.1 Antenna Cables 4.5.2 Electro-staticIssues 4.5.3Antenna Surge Protector Kit 5.Software Setup 5.1Point-to-point 5.2 Point-to-multipoint 5.3 Example Setups 5.3.1Direct PC to RF400 Series Base Station Setup Page 5.3.2Remote Station Setup Page 5.3.3 LoggerNet Configuration 5.3.4PC208W Configuration Page 6. Troubleshooting Page Page Appendix A. Part 15 FCC Compliance Warning Page Appendix B. Setup Menu B-2 B-3 B-4 Appendix C. RF400 Series Address and Address Mask Combined Network/ Radio Addresses C-2 C-3 C-4 Appendix D. Advanced Setup Standby Modes D-2 Appendix E. RF400 Series Port Pin Descriptions CS I/O FUNCTION E-2 Appendix F. Datalogger RS-232Port to RF400 Series Radio Page Appendix G. Short-HaulModems G-2 Appendix H. Distance vs. Antenna Gain, Terrain, and Other Factors Overview Link Analysis Transmitter Power Cable Loss Antenna Gain Receiver Sensitivity Path Loss Real World Distance Estimates Examples Range from ~9 to ~22 miles Range from ~14 to 30+ H-8 Appendix I. Phone to RF400 Series Page 2)AT Command Character: “-” Page Appendix J. Monitor CSAT3 via RF400 Series J-2 J-3 Page Appendix K. RF400/RF410 Pass/Fail Tests TESTING SC12 CABLE and PC COM PORT K-2 TESTING RF400/RF410s TESTING ANTENNAS K-5 TABLE K-1.900 MHz Gain Antenna Test Distances Antenna Power Ratio Distance Apart Over ¼ Wave Appendix L. RF400/RF410 Average Current Drain Calculations L-2 EXAMPLE #1 It ≈ 6.1 mA L-3 EXAMPLE #2 It ≈ 6.9 mA L-4 EXAMPLE #3 It ≈ 12.4 mA L-5 EXAMPLE #4 It ≈ 2.4 mA L-6 EXAMPLE #5 It ≈ 4.1 mA L-7 EXAMPLE #6 It ≈ 0.6 mA L-8 EXAMPLE #7 It ≈ 0.43 mA L-9 L-10 Page Campbell Scientific Companies Campbell Scientific, Inc. (CSI) Campbell Scientific Africa Pty. Ltd. (CSAf) Campbell Scientific Australia Pty. Ltd. (CSA) Campbell Scientific do Brazil Ltda. (CSB)