Conexant Systems 36342U Spread Spectrum Transmitter User Manual AN9949
Conexant Systems Inc. Spread Spectrum Transmitter AN9949
Contents
- 1. Manual
- 2. Addendum to manual
Manual
| Download: |  |
| Mirror Download [FCC.gov] | |
| Document ID | 162113 |
| Application ID | z7JAdz9blOx+WRrefE9ggw== |
| Document Description | Manual |
| Short Term Confidential | No |
| Permanent Confidential | No |
| Supercede | No |
| Document Type | User Manual |
| Display Format | Adobe Acrobat PDF - pdf |
| Filesize | 83.6kB (1044972 bits) |
| Date Submitted | 2001-07-30 00:00:00 |
| Date Available | 2001-07-30 00:00:00 |
| Creation Date | 2001-06-04 12:45:51 |
| Producing Software | Acrobat Distiller 4.05 for Windows |
| Document Lastmod | 2001-06-20 14:37:28 |
| Document Title | AN9949 |
| Document Creator | FrameMaker 6.0 |
| Document Author: | Intersil Corporation |
ISL36342U-EVAL PRISM II 11Mbps USB Wireless LAN Evaluation Kit User’s Guide TM Application Note June 2001 AN9949 Author: Richard L. Abrahams Introduction This kit allows evaluation of the Intersil PRISM® II Direct Sequence chip set design in a Wireless Local Area Network (WLAN) USB Card implementation. Software drivers are included allowing data to be transmitted between cards at 1, 2, 5.5 and 11Mbps transfer rates, with a diagnostic program to display the real data throughput from system to system. Your PC Card Wireless LAN Evaluation Kit contains the following items: QUANTITY DESCRIPTION PRISM II Wireless LAN PC Cards ISL36342U Wireless LAN Evaluation Kit User’s Guide, AN9949 PRISM II Chip Set Data Sheets PRISM II Application Notes Microsoft® Windows® 98, 98SE, MS, Win2000 Drivers PRISM® Test Utilities (PTU) Software Features/Benefits Card Product Registration Form Notification Card IN The IEEE 802.11 standard describes Media Access Control (MAC) procedures. The principal method of communication is the Carrier Sense Multiple Access with Collision Avoidance (CSMA-CA) protocol. Using this protocol, each station senses the communications medium (RF channel), and does not transmit until the channel is clear. This avoids collisions and minimizes the retransmission of subsequent packets. Included in the kit are PRISM II chip set data sheets with application notes describing the implementation of a wireless networking card using the chip set. Contents of Your Evaluation Kit An ad hoc communications network is created quickly and informally for a temporary time period. An infrastructure network usually requires more planning so that wireless stations can communicate over longer distances through access points, and may also communicate with existing wired LANs using portals. The standard also supports the operation of a station within a wireless LAN that may coexist with several overlapping wireless LANs. To accomplish this, a scheme of channelization and spread spectrum techniques is used. Direct Sequence (DSSS) and Frequency Hopping (FHSS) spread spectrum techniques are supported by the standard and both operate in the 2.4GHz to 2.4835GHz frequency band (the unlicensed ISM band). An infrared technique is also supported for indoor applications. The standard supports a 1Mbps and 2Mbps data rate for both DSSS and FHSS and has recently introduced a high data rate standard supporting 5.5Mbps and 11Mbps DSSS using Complementary Code Keying (CCK) modulation. The standard has also specified the requirements and services that enable private and secure communications to occur. Wireless LAN Configurations Should you discover that your PC Card Wireless LAN Evaluation Kit is incomplete, please contact Intersil Corporation. Overview of IEEE 802.11 The IEEE 802.11 specification is a standard for wireless connectivity for fixed, portable, and moving stations within a local area. The IEEE 802.11 standard describes the services required by a compliant device to operate within an “ad hoc” or “infrastructure” network, as well as dealing with the issues related to mobility within those networks. Spread spectrum techniques are used to tolerate mobility and multipath effects. They are also a requirement for compliance with FCC, ETSI and those of other regulatory authorities when operating within the Industrial, Scientific, and Medical (ISM) frequency band. For ease of use in evaluating these cards, an ad hoc network for peer to peer communications can be created. An ad hoc network is usually created for a specific purpose (such as file transfer or accessing a database). Ad hoc networks simplify the process of creating and dissolving networks for nontechnical users of the network facilities. Two cards form an IEEE 802.11 Independent Basic Service Set (IBSS), the simplest ad hoc network. The cards communicate with each other directly and must remain within radio range. When both cards are on, they immediately “see” each other and the ad hoc network is formed without user intervention. To use the cards in an infrastructure BSS (also called an Extended Service Set) where the two cards may not be in direct radio contact, access points are needed. The association between a card (station) and an infrastructure BSS - where communication occurs only between a station and an access point and not between stations directly is dynamic. Microsoft® Windows® and Windows NT® are registered trademarks of Microsoft Corporation. LINUX® is a registered trademark of Linus Torvalds. | Intersil and Design is a trademark of Intersil Americas Inc. Copyright © Intersil Americas Inc. 2001, All Rights Reserved PRISM® is a registered trademark of Intersil Americas Inc. PRISM and design is a trademark of Intersil Americas Inc. 1-888-INTERSIL or 321-724-7143 Application Note 9949 The IEEE 802.11 protocols are implemented in the firmware so that file transfers or database access can begin immediately. Direct Sequence Spread Spectrum Approach The use of spread spectrum techniques for wireless computer communications is widely accepted because of its robustness against multipath effects and interference from intentional or unintentional radiators. The use of spread spectrum techniques in the ISM frequency band also allows products to be deployed without the need for an FCC license. The two main methods by which spread spectrum communications can be achieved are Direct Sequence Spread Spectrum (DSSS) and Frequency Hopping Spread Spectrum (FHSS). This wireless LAN PC card uses the DSSS technique. DSSS transmission has the best performance in terms of multipath immunity and jamming rejection. In an office environment, jamming sources are likely to be unintentional such as emissions from microwave ovens. Even though unintentional, they pose a threat to the communications network. Direct sequence techniques are superior to frequency hopping systems in this case because FHSS gains its immunity to jamming by avoiding the location of a single tone jammer (such as other FHSS users). When collisions occur, data is lost. With a DSSS system, the despreading function in the receiver gives immunity to jamming by spreading the interfering energy by the Pseudo Random Number (PN) code over the whole bandwidth. This selective despreading attenuates the jamming power while despreading the desired signal. In the office environment, multipath effects may degrade network communications. Direct sequence techniques offer better protection than slower frequency hopping systems in the presence of multipath interference. With frequency hopped systems, if the hopper jumps to a frequency where a null resides, then data is lost until the next hop. Multipath signals can be thought of as a special case of unintentional jamming. In the DSSS approach, nulls resulting from multipath fading only eliminate a fraction of the signal power since the bandwidth in the DSSS case is very large. A significant amount of energy still remains in the signal and effective despreading still occurs. The probability of burst errors is reduced significantly. An often overlooked factor when comparing IEEE 802.11 compliant DSSS and FSSS implementations, is the achievable data rate. A frequency hopping occupied bandwidth of 1MHz as specified by the FCC acts as a limitation when using data rates beyond 2Mbps. A similar bandwidth limitation has not been imposed when using the direct sequence implementation. In the new 802.11 high data rate (11Mbps) standard utilizing Complementary Code Keying (CCK) modulation, the 5-1/2 times increase in data rate has been achieved in the same 17MHz bandwidth! This is accomplished by encoding 6 bits of data in one out of a possible 64 orthogonal PN spreading sequences. More information on the new high data rate standard may be found in Applications Note AN9850 “Complementary Code Keying Made Simple” which may be found on the Intersil Web Site. Installation of ISL36342U Windows Drivers Step 1. Boot your PC under Microsoft Windows. Step 2. Once your system has booted and is idle, insert PRISM II Driver for Windows, Disk #1 into the “A” Floppy Drive. On the Desktop, left click on-> then type A:SETUP Follow the on-screen instructions. Accept all defaults. Step 3. When the preliminary installation is complete, connect the wireless LAN PC card to the computer via the USB cable. Step 4. Windows should automatically recognize that the card has been inserted. It then displays a dialog box titled “New Hardware Found”. Step 5. Insert PRISM II Driver for Windows, Disk #1 into the floppy drive. Tell Windows that the driver is located on drive “A”. Accept all defaults. Step 6. Follow the on-screen instructions to complete installation of the driver. When complete, the NDC driver icon should appear in the system area on the desktop (computer monitor with antenna). Clicking on this icon enables setting of channel, mode, etc. Step 7. If operating in the Pseudo IBSS mode, you must assign a unique IP address to the computer in order for the card to be operable. Left click on -> -> . Double click on Network. Select TCP/IP ... PRISM IEEE 802.11 PC Card .... and click on Properties. Select the IP Address tab. Click on Obtain an IP Address. Enter a valid IP address. Enter a valid Subnet Mask (suggest 255 255 255 0). Click on OK. PRISM Test Utility (PTU) Software Installation NOTE: Perform after Windows Driver Installation. Step 1. Insert the PTU disk #1 into the floppy drive. Step 2. On the Desktop, left click on -> then type A:setup . Follow the on-screen instructions. Accept all defaults. When the installation is complete, an icon should automatically appear on the Desktop. Application Note 9949 PC Card Evaluation This chapter describes several software programs supplied with the kit. It also details some diagnostic test points that may be accessed on the card. Using the PRISM Test Utility (PTU) Software The PTU permits continuous operation of the transmitter. It is therefore convenient for performing RF measurements such as Transmitter Power. It also provides a handy method of changing channels within the ISM band, Use of the PRISM Transmitter Test Utility is basically self explanatory. An icon was automatically created on the desktop when the PTU installation was performed. It may be run by double-clicking on this icon. Using the LANEVAL Software normally run in the Pseudo IBSS mode as this provides a simple wireless Ad Hoc link between two computers. The NDC Driver may be easily accessed by double-clicking on its icon (looks like a computer with an antenna on top) located in the System Tray area on the desktop. List of Test Instruments The following instruments may be used for conducting tests on the wireless LAN PC card. INSTRUMENT MANUFACTURER MODEL Spectrum Analyzer Hewlett-Packard 8595E Power Meter Giga-tronics 8541B Signal Generator Hewlett-Packard 8648C LANEVAL provides a convenient method of analyzing Packet Error Rate (PER) and Receiver Sensitivity. An icon for starting LANEVAL was automatically placed on the desktop when the PTU installation was performed. In order for LANEVAL to form a successful link, the same packet parameters (e.g., Packet Length, Packet Pad Words, etc.) most be programmed at each end of the link. Frequency Counter Hewlett-Packard Differential Probe Tektronix P6247 LANEVAL runs in conjunction with the NDC Driver. The Driver permits selection of Data Rate and Channel. It is RF Probe, 500Ω Hewlett-Packard 54006A + 11742A 53181A (012 Option) Digital Scope General-Purpose Multimeter Computer with a USB Connection Slot (2 Required) 4 OSC 44MHz HFA3983 (FILE #4635) PA PLL VCTRL VCO BUFFER RF LO HFA3683A (FILE #4634) RF/IF CONVERTER I/Q LO VCO IF LO TX DAC TX ADC Q DAC I DAC TX ALC MOD AND FILTER I/O RAKE AND DEMOD AGC CTL CONTROL TEST I/O FIGURE 1. WIRELESS LAN PC CARD BLOCK DIAGRAM VCTRL HFA3783 (FILE #4633) IF I/Q MOD/DEMOD PLL REF_OUT Q ADC I ADC RF DAC RF ADC IF DAC HFA3863 BBP (FILE #4868.1) GP SERIAL PORTS RADIO CONTROL PORTS RADIO DATA INTERFACE USB INTERFACE LOGIC EXTERNAL MEMORY MEMORY ACCESS ARBITER 16-BIT PIPELINED CONTROL PROCESSOR CPU WEP ENGINE HFA3842 MAC (FILE #4839) 48MHz OSC Application Note 9949 USB INTERFACE TP6 J3 TP3 TP9 C149 TP1 C131 USB Attached P1 TP7 R85 L26 TP2 TP4 C119 C64 X1 C148 TP5 USB D- USB D+ C152 C122 C138 TP10 R95 R72 R92 C146 R90 C4 TP14 Q1 TP11 TP15 C147 vReg +3.3V C145 R91 R93 R94 C14 C9 C18 C31 R13 U5 C2 R33 R12 C139 L3 C20 R8 T6 T7 R7 T4 T8 T1 R28 C26 C25 R20 R30 C30 C32 T2 R34 T3 T5 C13 R2 C15 C144 C6 C33 L1 R83 TP13 R15 C143 C5 C10 R96 C24 U6 U6 U4 U1 REV B ISL36342U-EVAL 48 MHz U2 U2 TEST POINT L1 - RX Q- SIGNAL TEST POINT L - RX Q+ SIGNAL TEST POINT K1 - RX I- SIGNAL TEST POINT K- RX I+ SIGNAL ASSEMBLY TOP S/N R24 L29 TP12 U4 C1 FIGURE 2. WIRELESS LAN PC CARD TEST POINTS (TOP VIEW) DATE:23/OCT/00 R22 C36 C21 ISL36342U-EVAL REV B PRISMII RADIO USBUS INTERSIL CORP0RATION C11 R29 R27 R23 R19 C140 R18 R4 R1 C7 R14 D2 L28 U18 TP8 C3 C150 L25 L27 C8 C12 C17 R42 C34 C29 U3 C35 R16 R32 C19 R74 L21 R82 C27 Test Point Diagrams R3 D4 J1 Application Note 9949 L24 6 C65 FL3 L4 C66 R43 R73 C83 R37 C60 C67 C114 R51 C54 L8 C101 C98 L11 C105 R46 R53 C77 C151 C97 C130 U13 C133 U15 C100 C136 C50 C135 R44 R75 R76 C109 C69 R77 C62 C117 C116 C23 R65 C123 C125 R69 C95 C94 R35 C115 FL5 C113 R60 R68 R71 C126 C128 L19 L20 C127 L2 FIGURE 3. WIRELESS LAN PC CARD TEST POINTS (BOTTOM VIEW) C137 R55 TEST POINT F - RF L.O. TEST POINT G RF L.O. LOCK VOLTAGE C111 R66 C132 C74 U16 R63 C129 U14 C108 C118 C107 C124 C120 C110 R25 L14 U11 C51 C104 C112 R31 C58 C78 R56 U9 R64 INSTALL FOR RF CONNECTOR C141 (150 PF) ALSO INSTALL C137 (SEE ABOVE) C68 C103 R52 L9 R84 C89 C80 C56 R47 R62 R58 C93 R45 C102 TEST POINT B TX Q+ TEST POINT B1 TX Q- L22 C142 U17 TEST POINT A1 TX I- TEST POINT A TX I+ TEST POINT H IF L.O. TEST POINT I IF L.O. LOCK VOLTAGE R61 R57 R49 C88 C85 C70 R59 REMOVE FOR RF CONNECTOR L4 (1.5 NH) C79 C91 C84 U9 L17 U12 C87 C106 C61 U12 C73 C96 FL4 C99 C75 R54 R36 C82 C63 C92 R81 C141 R38 U11 L5 C59 C44 C86 L10 R50 C16 R40 C57 L16 R48 L6 C72 C81 C90 L13 C53 C76 U7 C41 U8 FL1 C46 C40 C42 C52 U10 L12 R80 C39 R39 C47 C45 C38 C71 C28 C22 C49 L7 FL1 TEST POINT C TX IF SIGNAL (BEFORE SAW FL) TEST POINT D - TX IF SIGNAL (AFTER SAW FL) C55 C48 INSTALL FOR RF CONNECTOR C137 (150 PF) ALSO INSTALL C141 (SEE BELOW) TEST POINT J- RX IF+ SIGNAL C43 C37 L15 (Continued) P1 J1 RF IN/OUT TEST POINT E (INSTALL J1 FOR RF CONNECTOR) Test Point Diagrams J3 Application Note 9949 C121 R67 R70 C134 L18 Application Note 9949 HFA 3683A HFA 3783 Diversity Switch UPG-152TA 1dB IL OCP 27 OIP3 50 Lowpass Filter LTF3216L 1dB IL Bandpass Filter USN 30172450 2dB IL LNA/Image Rejection Mixer Gain 25 dB NF 3.7dB OCP -7.5 OIP3 12 T/R Switch UPG-152TA 1dB IL OCP 27 OIP3 50 374MHz Saw Filter 8.5dB IL HFA 3783 Gain 61 NF 7dB OCP -14.3 OIP3 1.5 FIGURE 4. Receiver Noise/Gain Analysis The ISL36342U is implemented on FR-4 material. It uses 50Ω coplanar micro-strip traces which have a loss of 0.35dB/in at 2.442GHz. These losses are small, but should be considered when calculating the overall noise figure. The ISL36342U uses two diversity antennas. The first component is the antenna diversity select switch. This has an insertion loss of 1dB. The input trace to the switch along with the matching network associated with the switch brings the insertion loss to 2dB. The next component is a low pass filter. This filter provides transmit harmonic suppression. Its insertion loss is 1dB including the trace loss and matching loss from T/R switch. The next component is a bandpass filter. This filter limits the front end pass band to the ISM band, and provides out-of-band rejection for all undesired signals (e.g., cell phones). The filter characteristic is shown is Figure X. The insertion loss from this filter is 2.5dB including the effect of trace length. The bandpass filter is followed by a Transmit/Receive (T/R) switch. This switch connects the LNA or the Power Amplifier (PA) to the antennas. The insertion loss from this switch is 2.5dB including the effects of trace lengths and matching components. The LNA is the next component in the receive path. The LNA is inside the HFA3683A RF/IF converter and synthesizer, which also contains a image reject mixer, as well as the frequency synthesizer for the first Local Oscillator (LO). The first LO is low side injected to mix the desired channel to the Intermediate Frequency (IF) of 374MHz. The first LO tunes in 5MHz steps and is 374MHz below the ISM band channels. The first LO tune from 2038MHz to 2110MHz. The cascaded noise figure and gain of the LNA and the image reject mixer in the high gain mode is 3.7dB and 25dB respectively. The IF filter is a Surface Acoustic Wave (SAW) filter. The passband of the SAW filter is ±10MHz which provides adjacent channel rejection. It has linear phase, sharp attenuation characteristics and provides 50dB of ultimate suppression. The final component is the HFA3783 I/Q modulator/demodulator and synthesizer. The HFA3783 contains AGG amplifiers and a quadrature baseband converter. The HFA3783’s maximum gain is 61dB while the worst case noise figure is 8dB. The HFA3783 provides complex I and Q filtered inputs to the base-band processor. A spread sheet showing the noise gain analysis is shown in Figure X. In the low gain, mode the LNA gain is switched via the AGC to -9dB of loss. The noise gain cascade for the low gain mode is shown in Figure X. FIGURE 5. INPUT FILTER FIGURE 6. SAW FILTER Application Note 9949 TABLE 1. HIGH GAIN PARAMETERS PART REFERENCE NF GAIN OCP OIP3 CUM NF CUM GAIN ICP OIP3 IIP3 UPG152TA -2 27 50 2.00 -2 29 50.00 52.00 LTF3216L -1 99 99 3.00 -3 29 49.00 52.00 LFSN30172450 -2 99 99 5.00 -5 29 47.00 52.00 UPG152TA -2 27 50 7.00 -7 29 43.81 50.81 HFA3683A 3.7 25 -7.5 12 10.70 18 -25.5 12.00 -6.00 SAW374M 8.5 -8.5 99 99 10.74 9.5 -25.5 3.50 -6.00 HFA3783 61 -14.3 1.5 10.90 70.5 -84.8 1.50 -69.00 TABLE 2. LOW GAIN PARAMETERS PART REFERENCE NF GAIN OCP OIP3 CUM NF CUM GAIN ICP OIP3 IIP3 UPG152TA -2 27 50 2.00 -2 29 50.00 52.00 LTF3216L -1 99 99 3.00 -3 29 49.00 52.00 LFSN30172450 -2 99 99 5.00 -5 29 47.00 52.00 UPG152TA -2 27 50 7.00 -7 29 43.81 50.81 HFA3683A 3.7 -9 -7.5 12 10.70 -16 8.5 11.98 27.98 SAW374M 8.5 -8.5 99 99 24.04 -24.5 8.5 3.48 27.98 HFA3783 -72 -14.3 1.5 31.41 -96.5 8.5 -68.52 27.98 Explanation of Test Points Test Points A- A1, and B-B1 All measurements were taken using the “Continuous Transmit” or “Continuous Receive” features of the PTU diagnostic software. Unless otherwise noted, spectrum measurements included in this section were obtained using a Hewlett-Packard 54006A 500Ω probe and 11742A coaxial blocking capacitor and do not indicate the actual amplitude of the signal owing to losses associated with the probe. Unless noted, 11Mbps CCK modulation was employed. Transmit I and Q: Many of the signals are differential (i.e., balanced with respect to ground). These are denoted by + (plus) and - (minus) symbols following the signal name (e.g., RX I+ and RX I-). FIGURE 7. TRANSMIT I AND Q SIGNALS AT THE OUTPUT OF THE HFA3861 (TEST POINTS A-A1 AND B-B1) NOTE: BPSK mode is used for the plots in this figure. Therefore, I and Q are identical. Application Note 9949 The I and Q are both differential signals and, as such, consist of I+, I-, Q+, and Q- respectively. As these are balanced signals, data is measured using a Tektronix P6247 Differential Probe. For example in the measurement of the I signal, the probe is bridged between Test Points A (I+) and A1 (I-). Test Point E RF Transmit Signal: Transmit In-phase and Quadrature (I+ and Q+) signals are the spread baseband single-bit I and Q digital data that are outputted at the programmed chip rate (N). Test Points C and D IF Transmit Signal: FIGURE 10. TRANSMITTED 2.4GHz SIGNAL SPECTRUM (TEST POINT E) The optional SMA connector can be used to hook up a Spectrum Analyzer for RF evaluation. Note that L4 (1.5nH) must be removed and C141 (15pF) and C37 (150pF) must be installed to activate the connector See (Figure 3). FIGURE 8. IF TRANSMIT SIGNAL BEFORE SAW FILTER (TEST POINT C) This is the up-converted spread spectrum output of the card. The center frequency of this signal is 2412-2484MHz depending on the channel of operation. The output power of the signal is approximately +12.5dBm. The peaks of the sidelobes of the output spectrum (i.e., the regrowth) are normally adjusted by the ALC/AGC to be 30dB below the peak of the spectrum per requirements of IEEE 802.11. The following table delineates the IEEE 802.11 channels and their corresponding center frequencies. Although information contained in Table 1 is deemed to be accurate, local regulatory authorities should be consulted before using such equipment. TABLE 3. IEEE 802.11 CHANNELS FIGURE 9. IF TRANSMIT SIGNAL AFTER THE SAW FILTER (TEST POINT D) CHANNEL NUMBER CHANNEL FREQUENCY GEOGRAPHIC USAGE 2412MHz US, CA, ETSI, MKK 2417MHz US, CA, ETSI, MKK 2422MHz US, CA, ETSI, MKK 2427MHz US, CA, ETSI, MKK 2432MHz US, CA, ETSI, MKK 2437MHz US, CA, ETSI, MKK 2442MHz US, CA, ETSI, MKK 2447MHz US, CA, ETSI, MKK 2452MHz US, CA, ETSI, MKK 10 2457MHz US, CA, ETSI, FR, SP, MKK The intermediate frequency (IF) transmit signal is a spread spectrum signal centered at 374MHz with a 17MHz bandwidth. 11 2462MHz US, CA, ETSI, FR, SP, MKK 12 2467MHz ETSI, FR, MKK 13 2472MHz ETSI, FR, MKK The SAW filter is used to shape the sidelobes. 14 2484MHz Japan† Test point C is at the input of the SAW Filter whereas D is at the output. KEY: US = United States, CA = Canada, ETSI = ETSI countries (except France and Spain), FR = France, SP = Spain. † In Japan, Channel 14 requires Japanese Transmit Filter. Application Note 9949 Test Points F and G Test Point J RF local oscillator (LO): IF Receive Signal: FIGURE 11. RF LOCAL OSCILLATOR OUTPUT AT CHANNEL 8 (TEST POINT F) The behavior of the RF VCO can be monitored at Test Point F. The VCO output should be locked at the channel frequency minus the IF (374MHz.) This means that the VCO will have to lock between 2038MHz and 2110MHz. The output power at test point F is approximately -6dBm. Ideally, the tuning voltage of the VCO, when locked, falls between 0.5V and 2.2V. The tuning voltage of the RF VCO can be observed at Test Point G. Test Points H and I IF local oscillator (LO): FIGURE 13. IF RECEIVE SIGNAL PRIOR TO SAW FILTER (TEST POINT J) The intermediate frequency (IF) receive signal is the downconverted receive signal prior to the SAW bandpass filter. The center frequency of this signal is 374MHz with a bandwidth of 17MHz. The power of this signal is directly dependent on the input signal power. Note that the spurious signal visible below the DS spectrum’s frequency is a harmonic of the 44MHz clock. Much of this level is due to stray pickup in the 500Ω RF probe because of the relatively low signal level present. As such, it will have no influence on receiver performance. Test Point K-K1 and L-L1 Receive I and Q: FIGURE 12. IF LOCAL OSCILLATOR OUTPUT (TEST POINT H) The IF VCO is a discrete design and operates at 748MHz (i.e., twice the IF frequency). The output frequency of this VCO does not need to be varied; thus, minimal tuning range is required. The output frequency of this VCO can be observed at Test Point H. FIGURE 14. RECEIVE I AND Q SIGNALS (TEST POINTS K AND L) Ideally, the tuning voltage of the IF VCO, when locked, falls between 0.5V and 2.2V. The tuning voltage of the IF VCO can be observed at Test Point I. NOTE: BPSK mode is used for the plots in this figure; as such, I and Q are inverse of each other. 10 Application Note 9949 The receive In-phase and Quadrature (I and Q) signals are the demodulated lowpass-filtered data that are coupled to the HFA3861. The output levels of these two signals are approximately 500mVP-P. As these are balanced signals, data is taken using a Tektronix P6247 Differential Probe. • Test point K for RXI+ signal is at the 0Ω jumper, R19. • Test point K1 for RXI- signal is at the 0Ω jumper, R23 TABLE 4. GENERAL SPECIFICATIONS SPECIFICATION VALUE IF Bandwidth 17MHz RX/TX Switching Speed 2µs (Typ) Average Current without Power Save 2% Transmit, 98% Receive 187mA (Typ) Average Current with Power Save 2% TX, 8% RX, 90% Standby 43mA (Typ) Current in Continuous TX mode 300mA (Typ) Current in Continuous RX Mode 185mA (Typ) Standby Current 25mA (Typ) Mechanical PC Card, with Antenna Extension Output Power +11.5dBm (Typ) Transmit Spectral Mask -30dBc at First Side Lobes Antenna Interface SMA, 50Ω (for Testing Only) Dual Diversity Printed Antenna • Test point L for RXQ+ signal is at the 0Ω jumper, R27 • Test point L1 for RXQ- signal is at the 0Ω jumper, R29. 1.875" FIGURE 15. EDGE VIEW, USB CARD Absolute Maximum Ratings Supply Voltage . . . . . . . . . . . . . . . . . . . . . . . . . . -0.3V to 7.0V (Max) Storage Temperature (Note 1) . . . . . . . . . . . . . . . . . . -20oC to 65oC Operating Conditions Temperature Range . . . . . . . . . . . . . . . . . . . . . . . . 0oC ≤ TA ≤ 55oC Supply Voltage Range . . . . . . . . . . . . . . . . . . . . . . . . . . 4.20V to 7V Caution: These are the absolute maximum ratings for the PC Card product. Exceeding these limits could cause permanent damage to the card. References For Intersil documents available on the internet, see web site www.intersil.com [1] iSL36342U-EVAL Data Sheet, Intersil Corporation. [2] AN9850 Application Note, Intersil Corporation, “Complementary Code Keying Made Simple”. Notices NOTE: 1. All temperature references refer to ambient conditions. This device complies with Part 15 of the FCC rules. Operation is subject to the following two conditions: Operational Characteristics See the iSL36342U-EVAL data sheet, Intersil File Number FN8018, for more detailed specifications. TABLE 4. GENERAL SPECIFICATIONS SPECIFICATION VALUE Targeted Standard IEEE 802.11 Data Rate 1Mbps DBPSK 2Mbps DQPSK 5.5Mbps CCK 11Mbps CCK Range (11Mbps Data Rate) 120ft (37M) Indoor (Typ) 400ft (122M) Outdoor (Typ) Center Frequency Range 2412MHz - 2484MHz Step Size 1MHz IF Frequency 374MHz 11 Electronic Emission Notices 1. This device may not cause harmful interference. 2. This device must accept any interference received, including interference that may cause undesired operation. FCC Radio Frequency Interference Statement The wireless LAN PC card is subject to the rules of the Federal Communications Commission (FCC). This card is considered an intentional radiator as per the FCC guidelines. NOTE: This equipment has been tested and found to comply with the limits for a Class B digital device, pursuant to Part 15 of the FCC rules. These limits are designed to provide reasonable protection against harmful interference in a residential installation. This equipment generates, uses and can radiate radio frequency energy and, if not installed and used in accordance with the instruction manual, may cause harmful interference to radio communications. However, there is no guarantee that interference will not occur in a particular installation. If this equipment does cause harmful Application Note 9949 interference to radio or television reception, which can be determined by turning the equipment off and on, the user is encouraged to try to correct the interference by one or more of the following measures: WARNING! Any changes or modifications of equipment not expressly approved by Intersil could void the user’s authority to operate the equipment. • Reorient or relocate the receiving antenna • Increase the separation between the equipment and the receiver • Connect the equipment into an outlet on a circuit different from that to which the receiver is connected • Consult the dealer or an experienced ratio/TV technician for help Packaging All Intersil products are manufactured, assembled and tested utilizing ISO9000 quality systems. Intersil Corporation’s quality certifications can be viewed at website www.intersil.com/design/quality Intersil products are sold by description only. Intersil Corporation reserves the right to make changes in circuit design and/or specifications at any time without notice. Accordingly, the reader is cautioned to verify that data sheets are current before placing orders. Information furnished by Intersil is believed to be accurate and reliable. However, no responsibility is assumed by Intersil or its subsidiaries for its use; nor for any infringements of patents or other rights of third parties which may result from its use. No license is granted by implication or otherwise under any patent or patent rights of Intersil or its subsidiaries. For information regarding Intersil Corporation and its products, see web site www.intersil.com 12
Source Exif Data:
File Type : PDF File Type Extension : pdf MIME Type : application/pdf PDF Version : 1.3 Linearized : No Producer : Acrobat Distiller 4.05 for Windows Create Date : 2001:06:04 12:45:51 Creator : FrameMaker 6.0 Keywords : Intersil Corporation, semiconductor, Wireless Communications, RF, Radio Frequency, IF, Intermediate Frequency, Wireless LAN, Wireless Local Area Network, WLL, Wireless Local Loop, Wireless Ethernet, Home LAN, Home Local Area Network, MAC 11MBPS, Prism II, Prism 2, medium access controller Subject : ISL36342U-EVAL PRISM II 11Mbps USB Wireless LAN Evaluation Kit User’s Guide Author : Intersil Corporation Title : AN9949 Modify Date : 2001:06:20 14:37:28-04:00 Page Count : 12EXIF Metadata provided by EXIF.tools