Product Feature: GPS Diplexer by Lorch Microwave G satellites constantly circling mum over temperature. The 3 dB bandwidth is 100 MHz nominal. The Pass Band as previously stated is .5 tbe earth. These satellites transmit very low power radio signals allowing dB relative over tbe center 30 MHz (1212 to 1242). The Return loss is 14 PS or Global Positioning System refers to a group of anyone witb a GPS receiver to deter­ mine tbeir current location. Each satellite transmits on several frequen­ cies designated as L 1, L2, etc. The signals travel line of sight meaning they will pass through clouds, glass and plastic, bur will not go through most solid objects such as buildings and mountains. These line of sight sig­ nals are also susceptible to other inter­ fering signals such as US ATC Radar. Lorch Microwave has developed a fil­ ter to provide the teleco=unications industry with an of the shelf product that addresses the ever increasing fre­ quency interference problem with today's crowded frequency spectrum. ·1227t,575_,_, .OldB ripple Chebychev transfer of band attenuation. The Passband bandwidth is specified as .5 dB flat­ ness minimum over 30 MHz. A three pole filter response was chosen to provide adequate minimum size. attenuation and Typical performance for the 3DP91227/1575-M is shown in Figure 1: Of,"_._.. .-tD'•l .. . ....,.. _,,..... ... ...., . ... .. 13-.... ..... ... dB minimum and 17 dB typical over the center 30 MHz of the band. Isolation between the two channeIs is typically greater than 25 dB. The filter is packaged on an open Figure 1: 1227.6 MHZ less nickel gold plate on our carrier boards for ease of solder. We build ture connector configurations. We can provide the part in a hermetically sealed housing if tbe environmental function was chosen to provide mini­ mum insertion loss and maximum out 1. ,. .... ... . (1560 to 1590). The Return Joss is 14 mount GPS diplexer that has been Loss is typically the most important design concern as it directly affects the overall system noise figure. A •t..liW41 The 3 dB bandwidth is 100 MHz nominal. The Pass Band on the upper channel is also .5 dB relative over the center 30 MHz designed to provide excellent in band performance while achieving excel­ lent out of band attenuation in a small mechanical configuration. Insertion .. "•k-• ��l1dl au -l�-- typical and specified as 1.5 dB maxi­ mum over temperature. figuration. However, this ftlter can be made available in a variety of other custom packages with SMA or minia­ 3DP9-1227/1575-M is a surface ..... .. ... . the center 30 MHz of the band. Please see Figure 2: 1575.42 MHz. The upper band of the Diplexer is centered on 1575.42 MHz. The Insertion Loss at Mid Band is 1.3 dB our components with s/n 96 solder to withstand reflow conditions of 215°C for 15 seconds. The filter is suitable for various applications, both military and commerical. Lorch has designed this filter to be in a surface mount con­ GPS Diplexer 14148t15 dB minimum and 17dB typical over framed FR4 carrier PCB 1.25" long by .50" wide. The overall height of the package is .38". We use an electro­ UlJlfb 3DP9 - ' ".. 2..! v ...... .. L ....... ' ... '"' .... 11 �"' ••• 7 Mr 201S , . .....". liLt�· .1••••••2 UII .. MHI OHMr••,.._ lilt....., .. -l,..... Ntl ll1&.34d u. .... .... conditions warrant it. The typical operating temperature is -4o•c to +70•c. Lorch Microwave has tested these filters at the operating tempera­ CMlftar'tt.,... &JU•l '21"'.ltnt .. -u..... ,... ....41llcil 1S.MIIM4a. ture extremes of -40, +25, and +70 degrees Celsius. The typical tempera­ ture drift has been measured at less than I 0 ppM per degrees Celsius over the frequency and bandwidth. The 3DP9-1227/1575-M diplexer has also been used as ftltering for LNA (low noise amplifiers). By tak­ ing the diplexer and combining this unit with an LNA you are able to pro­ 1227.6 MHz. The lower band of the Diplexer is vide a GPS preamplifier with different gain variations as well as selectivity. The filter has very little affect to the centered on 1227.6 MHz. The Insertion Loss at Mid Band is 1.3 dB typical and specified as 1.5 dB maxi- low mid-band insertion loss. There are otber standard designs available that system overall noise figure due to the Figure 2: 1575.42 MHZ provide more selectivity with a slight increase in package size and insertion Joss. If you would like more informa­ tion on this product please feel free to contact Lorch Microwave at 410-860- 51 00 or visit our web www.lorchmicrowave.com. site at LORCH MICROWAVE CIRCLE READER SERVICE NO.